Integral $int_0^infty dp , fracp^5 sin(p x) e^-b p^2p^4 + a^2$: any clever ideas?

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I am trying to solve the following integral, with $a>0,$ $b>0$:



$I equiv int_0^infty dp , fracp^5 sin(p x) e^-b p^2p^4 + a^2 $



By expanding the $sin$, I get



$I = sum_n=1^infty fracx^2n-1(2n-1)! int_0^infty dp , fracp^4+2n e^-b p^2p^4 + a^2 \
= sum_n=1^infty fracx^2n-1(2n-1)!Bigg
frac12 b^frac32-n Gamma (n-3/2) , _1F_2left(1;frac54-fracn2,frac74-fracn2;-frac14 a^2 b^2right)
+frac14 pi a^n-frac32
left[csc left((2 pi n+pi )/4right] cos (a b)
-sec left[ (2 pi n+pi )/4right] sin (a b)right)
Bigg.$



Here $_1F_2$ is a hypergeometric function. The first summation can be done, so that we are left with



$I= fracpi2a left[cos (a b) cos (xsqrta/2) sinh (xsqrta/2)+sin (a b) sin (xsqrta/2) cosh (xsqrta/2)right]
+
sum_n=1^infty fracx^2n-1(2n-1)!
frac12 b^frac32-n Gamma (n-3/2) , _1F_2left(1;frac54-fracn2,frac74-fracn2;-frac14 a^2 b^2right).$



I am unable to find a closed form for the second summation.



Is there an easier way to solve $I$? Presumably one can apply the residue theorem, but I did not find a quick way. Any ideas would be appreciated!










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  • 4




    If I may ask, why is this integral interesting?
    – Sobi
    Sep 6 at 10:38






  • 1




    I'm trying to Fourier invert an expression, and this is the spatial (radially symmetric) part.
    – Can't integrate
    Sep 6 at 12:12














up vote
1
down vote

favorite












I am trying to solve the following integral, with $a>0,$ $b>0$:



$I equiv int_0^infty dp , fracp^5 sin(p x) e^-b p^2p^4 + a^2 $



By expanding the $sin$, I get



$I = sum_n=1^infty fracx^2n-1(2n-1)! int_0^infty dp , fracp^4+2n e^-b p^2p^4 + a^2 \
= sum_n=1^infty fracx^2n-1(2n-1)!Bigg
frac12 b^frac32-n Gamma (n-3/2) , _1F_2left(1;frac54-fracn2,frac74-fracn2;-frac14 a^2 b^2right)
+frac14 pi a^n-frac32
left[csc left((2 pi n+pi )/4right] cos (a b)
-sec left[ (2 pi n+pi )/4right] sin (a b)right)
Bigg.$



Here $_1F_2$ is a hypergeometric function. The first summation can be done, so that we are left with



$I= fracpi2a left[cos (a b) cos (xsqrta/2) sinh (xsqrta/2)+sin (a b) sin (xsqrta/2) cosh (xsqrta/2)right]
+
sum_n=1^infty fracx^2n-1(2n-1)!
frac12 b^frac32-n Gamma (n-3/2) , _1F_2left(1;frac54-fracn2,frac74-fracn2;-frac14 a^2 b^2right).$



I am unable to find a closed form for the second summation.



Is there an easier way to solve $I$? Presumably one can apply the residue theorem, but I did not find a quick way. Any ideas would be appreciated!










share|cite|improve this question

















  • 4




    If I may ask, why is this integral interesting?
    – Sobi
    Sep 6 at 10:38






  • 1




    I'm trying to Fourier invert an expression, and this is the spatial (radially symmetric) part.
    – Can't integrate
    Sep 6 at 12:12












up vote
1
down vote

favorite









up vote
1
down vote

favorite











I am trying to solve the following integral, with $a>0,$ $b>0$:



$I equiv int_0^infty dp , fracp^5 sin(p x) e^-b p^2p^4 + a^2 $



By expanding the $sin$, I get



$I = sum_n=1^infty fracx^2n-1(2n-1)! int_0^infty dp , fracp^4+2n e^-b p^2p^4 + a^2 \
= sum_n=1^infty fracx^2n-1(2n-1)!Bigg
frac12 b^frac32-n Gamma (n-3/2) , _1F_2left(1;frac54-fracn2,frac74-fracn2;-frac14 a^2 b^2right)
+frac14 pi a^n-frac32
left[csc left((2 pi n+pi )/4right] cos (a b)
-sec left[ (2 pi n+pi )/4right] sin (a b)right)
Bigg.$



Here $_1F_2$ is a hypergeometric function. The first summation can be done, so that we are left with



$I= fracpi2a left[cos (a b) cos (xsqrta/2) sinh (xsqrta/2)+sin (a b) sin (xsqrta/2) cosh (xsqrta/2)right]
+
sum_n=1^infty fracx^2n-1(2n-1)!
frac12 b^frac32-n Gamma (n-3/2) , _1F_2left(1;frac54-fracn2,frac74-fracn2;-frac14 a^2 b^2right).$



I am unable to find a closed form for the second summation.



Is there an easier way to solve $I$? Presumably one can apply the residue theorem, but I did not find a quick way. Any ideas would be appreciated!










share|cite|improve this question













I am trying to solve the following integral, with $a>0,$ $b>0$:



$I equiv int_0^infty dp , fracp^5 sin(p x) e^-b p^2p^4 + a^2 $



By expanding the $sin$, I get



$I = sum_n=1^infty fracx^2n-1(2n-1)! int_0^infty dp , fracp^4+2n e^-b p^2p^4 + a^2 \
= sum_n=1^infty fracx^2n-1(2n-1)!Bigg
frac12 b^frac32-n Gamma (n-3/2) , _1F_2left(1;frac54-fracn2,frac74-fracn2;-frac14 a^2 b^2right)
+frac14 pi a^n-frac32
left[csc left((2 pi n+pi )/4right] cos (a b)
-sec left[ (2 pi n+pi )/4right] sin (a b)right)
Bigg.$



Here $_1F_2$ is a hypergeometric function. The first summation can be done, so that we are left with



$I= fracpi2a left[cos (a b) cos (xsqrta/2) sinh (xsqrta/2)+sin (a b) sin (xsqrta/2) cosh (xsqrta/2)right]
+
sum_n=1^infty fracx^2n-1(2n-1)!
frac12 b^frac32-n Gamma (n-3/2) , _1F_2left(1;frac54-fracn2,frac74-fracn2;-frac14 a^2 b^2right).$



I am unable to find a closed form for the second summation.



Is there an easier way to solve $I$? Presumably one can apply the residue theorem, but I did not find a quick way. Any ideas would be appreciated!







calculus definite-integrals residue-calculus hypergeometric-function






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asked Sep 6 at 10:21









Can't integrate

547




547







  • 4




    If I may ask, why is this integral interesting?
    – Sobi
    Sep 6 at 10:38






  • 1




    I'm trying to Fourier invert an expression, and this is the spatial (radially symmetric) part.
    – Can't integrate
    Sep 6 at 12:12












  • 4




    If I may ask, why is this integral interesting?
    – Sobi
    Sep 6 at 10:38






  • 1




    I'm trying to Fourier invert an expression, and this is the spatial (radially symmetric) part.
    – Can't integrate
    Sep 6 at 12:12







4




4




If I may ask, why is this integral interesting?
– Sobi
Sep 6 at 10:38




If I may ask, why is this integral interesting?
– Sobi
Sep 6 at 10:38




1




1




I'm trying to Fourier invert an expression, and this is the spatial (radially symmetric) part.
– Can't integrate
Sep 6 at 12:12




I'm trying to Fourier invert an expression, and this is the spatial (radially symmetric) part.
– Can't integrate
Sep 6 at 12:12










2 Answers
2






active

oldest

votes

















up vote
1
down vote



accepted










We have
$$frac p^5 e^-b p^2 sin x p p^4 + a^2 =
p e^-b p^2 sin x p left( 1 +
frac i a 2 (p^2 - i a) - frac i a 2 (p^2 + i a) right), \
frac d db left( e^i a b int_0^infty
frac p e^-b p^2 sin x p p^2 - i a dp right) =
-e^i a b int_0^infty p e^-b p^2 sin x p ,dp,$$
and, after some calculations,
$$int_0^infty frac p^5 e^-b p^2 sin x p p^4 + a^2 dp =
F(a) + F(-a) + frac sqrt pi x e^-x^2/(4 b) 4 b^3/2, \
F(a) = frac i pi a e^i a b 8 left(
e^x sqrt i a operatornameerfc frac 2 b sqrti a + x 2 sqrt b -
e^-x sqrt i a operatornameerfc frac 2 b sqrti a - x 2 sqrt b
right).$$






share|cite|improve this answer




















  • This is great. Thank you so much. What an elegant and creative solution. I've checked it, and it's correct. May I ask how you came up with the idea? I guess partial fraction expansion of the main integral is the key.
    – Can't integrate
    Sep 14 at 15:02











  • Right, when there is a polynomial in the exponent and a polynomial in the denominator, differentiation under the integral sign often works, and, since we have $p^2$ in the exponent and $p^4$ in the denominator, that suggests applying partial fraction decomposition.
    – Maxim
    Sep 15 at 7:03


















up vote
2
down vote













Amazingly this integral can be solved in terms of well-known functions of mathematical physics. It is easy to see that
$$I(a,b,x):=int_0^infty fracp^5,sin(px)p^4+a^2,e^-b,p^2 dp =frac12 fracddb fracddx underbraceint_-infty^infty fracp^2,cos(px)p^4+a^2,e^-b,p^2 dp_:=J(a,b,x).$$
I won't do the derivatives, but present the formula for $J(a,b,x).$ Let $c=x/sqrt4b.$ Then
$$ J(a,b,x)=fracpi2sqrtb,e^-c^2,ReBig[frac1sqrti,a,b
Big( expbig( (sqrti,a,b - c)^2 big) , texterfcbig(sqrti,a,b - cbig) + $$
$$+ expbig( (sqrti,a,b + c)^2 big) , texterfcbig(sqrti,a,b + cbig) Big)Big] $$
The 'erfc' is the complimentary error function. My proof is long and not rigorous so we'll wait a few days to see if anyone will present a proof. If not, I may return to it. However, I've tested the numerical integration vs. the closed form for a total of 1000 evaluations for 10 different $a,, b, , x.$ The differences were 0 to within machine precision. The tests were over positive $a,, b, , x$ each from 0.1 to 6.5 by increments of 0.6.






share|cite|improve this answer




















  • Wow, I've looked at it numerically - and can't find any disagreements! :) Is your reasoning based on the residue theorem, or some other trick?
    – Can't integrate
    Sep 6 at 22:08






  • 1




    Briefly, I came up with another integral relationship that I started to estimate asymptotically. However, I recognized the asymptotic series could be summed in terms of the exp * erfc terms; hence the non-rigor. I'd be happy if someone would attempt a rigorous proof. One of the variables can be eliminated and probably a partial differential equation in two variables can be established that is satisfied by the integral form of J(a,b,x) and the closed form.
    – skbmoore
    Sep 6 at 22:44










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2 Answers
2






active

oldest

votes








2 Answers
2






active

oldest

votes









active

oldest

votes






active

oldest

votes








up vote
1
down vote



accepted










We have
$$frac p^5 e^-b p^2 sin x p p^4 + a^2 =
p e^-b p^2 sin x p left( 1 +
frac i a 2 (p^2 - i a) - frac i a 2 (p^2 + i a) right), \
frac d db left( e^i a b int_0^infty
frac p e^-b p^2 sin x p p^2 - i a dp right) =
-e^i a b int_0^infty p e^-b p^2 sin x p ,dp,$$
and, after some calculations,
$$int_0^infty frac p^5 e^-b p^2 sin x p p^4 + a^2 dp =
F(a) + F(-a) + frac sqrt pi x e^-x^2/(4 b) 4 b^3/2, \
F(a) = frac i pi a e^i a b 8 left(
e^x sqrt i a operatornameerfc frac 2 b sqrti a + x 2 sqrt b -
e^-x sqrt i a operatornameerfc frac 2 b sqrti a - x 2 sqrt b
right).$$






share|cite|improve this answer




















  • This is great. Thank you so much. What an elegant and creative solution. I've checked it, and it's correct. May I ask how you came up with the idea? I guess partial fraction expansion of the main integral is the key.
    – Can't integrate
    Sep 14 at 15:02











  • Right, when there is a polynomial in the exponent and a polynomial in the denominator, differentiation under the integral sign often works, and, since we have $p^2$ in the exponent and $p^4$ in the denominator, that suggests applying partial fraction decomposition.
    – Maxim
    Sep 15 at 7:03















up vote
1
down vote



accepted










We have
$$frac p^5 e^-b p^2 sin x p p^4 + a^2 =
p e^-b p^2 sin x p left( 1 +
frac i a 2 (p^2 - i a) - frac i a 2 (p^2 + i a) right), \
frac d db left( e^i a b int_0^infty
frac p e^-b p^2 sin x p p^2 - i a dp right) =
-e^i a b int_0^infty p e^-b p^2 sin x p ,dp,$$
and, after some calculations,
$$int_0^infty frac p^5 e^-b p^2 sin x p p^4 + a^2 dp =
F(a) + F(-a) + frac sqrt pi x e^-x^2/(4 b) 4 b^3/2, \
F(a) = frac i pi a e^i a b 8 left(
e^x sqrt i a operatornameerfc frac 2 b sqrti a + x 2 sqrt b -
e^-x sqrt i a operatornameerfc frac 2 b sqrti a - x 2 sqrt b
right).$$






share|cite|improve this answer




















  • This is great. Thank you so much. What an elegant and creative solution. I've checked it, and it's correct. May I ask how you came up with the idea? I guess partial fraction expansion of the main integral is the key.
    – Can't integrate
    Sep 14 at 15:02











  • Right, when there is a polynomial in the exponent and a polynomial in the denominator, differentiation under the integral sign often works, and, since we have $p^2$ in the exponent and $p^4$ in the denominator, that suggests applying partial fraction decomposition.
    – Maxim
    Sep 15 at 7:03













up vote
1
down vote



accepted







up vote
1
down vote



accepted






We have
$$frac p^5 e^-b p^2 sin x p p^4 + a^2 =
p e^-b p^2 sin x p left( 1 +
frac i a 2 (p^2 - i a) - frac i a 2 (p^2 + i a) right), \
frac d db left( e^i a b int_0^infty
frac p e^-b p^2 sin x p p^2 - i a dp right) =
-e^i a b int_0^infty p e^-b p^2 sin x p ,dp,$$
and, after some calculations,
$$int_0^infty frac p^5 e^-b p^2 sin x p p^4 + a^2 dp =
F(a) + F(-a) + frac sqrt pi x e^-x^2/(4 b) 4 b^3/2, \
F(a) = frac i pi a e^i a b 8 left(
e^x sqrt i a operatornameerfc frac 2 b sqrti a + x 2 sqrt b -
e^-x sqrt i a operatornameerfc frac 2 b sqrti a - x 2 sqrt b
right).$$






share|cite|improve this answer












We have
$$frac p^5 e^-b p^2 sin x p p^4 + a^2 =
p e^-b p^2 sin x p left( 1 +
frac i a 2 (p^2 - i a) - frac i a 2 (p^2 + i a) right), \
frac d db left( e^i a b int_0^infty
frac p e^-b p^2 sin x p p^2 - i a dp right) =
-e^i a b int_0^infty p e^-b p^2 sin x p ,dp,$$
and, after some calculations,
$$int_0^infty frac p^5 e^-b p^2 sin x p p^4 + a^2 dp =
F(a) + F(-a) + frac sqrt pi x e^-x^2/(4 b) 4 b^3/2, \
F(a) = frac i pi a e^i a b 8 left(
e^x sqrt i a operatornameerfc frac 2 b sqrti a + x 2 sqrt b -
e^-x sqrt i a operatornameerfc frac 2 b sqrti a - x 2 sqrt b
right).$$







share|cite|improve this answer












share|cite|improve this answer



share|cite|improve this answer










answered Sep 13 at 9:04









Maxim

2,595113




2,595113











  • This is great. Thank you so much. What an elegant and creative solution. I've checked it, and it's correct. May I ask how you came up with the idea? I guess partial fraction expansion of the main integral is the key.
    – Can't integrate
    Sep 14 at 15:02











  • Right, when there is a polynomial in the exponent and a polynomial in the denominator, differentiation under the integral sign often works, and, since we have $p^2$ in the exponent and $p^4$ in the denominator, that suggests applying partial fraction decomposition.
    – Maxim
    Sep 15 at 7:03

















  • This is great. Thank you so much. What an elegant and creative solution. I've checked it, and it's correct. May I ask how you came up with the idea? I guess partial fraction expansion of the main integral is the key.
    – Can't integrate
    Sep 14 at 15:02











  • Right, when there is a polynomial in the exponent and a polynomial in the denominator, differentiation under the integral sign often works, and, since we have $p^2$ in the exponent and $p^4$ in the denominator, that suggests applying partial fraction decomposition.
    – Maxim
    Sep 15 at 7:03
















This is great. Thank you so much. What an elegant and creative solution. I've checked it, and it's correct. May I ask how you came up with the idea? I guess partial fraction expansion of the main integral is the key.
– Can't integrate
Sep 14 at 15:02





This is great. Thank you so much. What an elegant and creative solution. I've checked it, and it's correct. May I ask how you came up with the idea? I guess partial fraction expansion of the main integral is the key.
– Can't integrate
Sep 14 at 15:02













Right, when there is a polynomial in the exponent and a polynomial in the denominator, differentiation under the integral sign often works, and, since we have $p^2$ in the exponent and $p^4$ in the denominator, that suggests applying partial fraction decomposition.
– Maxim
Sep 15 at 7:03





Right, when there is a polynomial in the exponent and a polynomial in the denominator, differentiation under the integral sign often works, and, since we have $p^2$ in the exponent and $p^4$ in the denominator, that suggests applying partial fraction decomposition.
– Maxim
Sep 15 at 7:03











up vote
2
down vote













Amazingly this integral can be solved in terms of well-known functions of mathematical physics. It is easy to see that
$$I(a,b,x):=int_0^infty fracp^5,sin(px)p^4+a^2,e^-b,p^2 dp =frac12 fracddb fracddx underbraceint_-infty^infty fracp^2,cos(px)p^4+a^2,e^-b,p^2 dp_:=J(a,b,x).$$
I won't do the derivatives, but present the formula for $J(a,b,x).$ Let $c=x/sqrt4b.$ Then
$$ J(a,b,x)=fracpi2sqrtb,e^-c^2,ReBig[frac1sqrti,a,b
Big( expbig( (sqrti,a,b - c)^2 big) , texterfcbig(sqrti,a,b - cbig) + $$
$$+ expbig( (sqrti,a,b + c)^2 big) , texterfcbig(sqrti,a,b + cbig) Big)Big] $$
The 'erfc' is the complimentary error function. My proof is long and not rigorous so we'll wait a few days to see if anyone will present a proof. If not, I may return to it. However, I've tested the numerical integration vs. the closed form for a total of 1000 evaluations for 10 different $a,, b, , x.$ The differences were 0 to within machine precision. The tests were over positive $a,, b, , x$ each from 0.1 to 6.5 by increments of 0.6.






share|cite|improve this answer




















  • Wow, I've looked at it numerically - and can't find any disagreements! :) Is your reasoning based on the residue theorem, or some other trick?
    – Can't integrate
    Sep 6 at 22:08






  • 1




    Briefly, I came up with another integral relationship that I started to estimate asymptotically. However, I recognized the asymptotic series could be summed in terms of the exp * erfc terms; hence the non-rigor. I'd be happy if someone would attempt a rigorous proof. One of the variables can be eliminated and probably a partial differential equation in two variables can be established that is satisfied by the integral form of J(a,b,x) and the closed form.
    – skbmoore
    Sep 6 at 22:44














up vote
2
down vote













Amazingly this integral can be solved in terms of well-known functions of mathematical physics. It is easy to see that
$$I(a,b,x):=int_0^infty fracp^5,sin(px)p^4+a^2,e^-b,p^2 dp =frac12 fracddb fracddx underbraceint_-infty^infty fracp^2,cos(px)p^4+a^2,e^-b,p^2 dp_:=J(a,b,x).$$
I won't do the derivatives, but present the formula for $J(a,b,x).$ Let $c=x/sqrt4b.$ Then
$$ J(a,b,x)=fracpi2sqrtb,e^-c^2,ReBig[frac1sqrti,a,b
Big( expbig( (sqrti,a,b - c)^2 big) , texterfcbig(sqrti,a,b - cbig) + $$
$$+ expbig( (sqrti,a,b + c)^2 big) , texterfcbig(sqrti,a,b + cbig) Big)Big] $$
The 'erfc' is the complimentary error function. My proof is long and not rigorous so we'll wait a few days to see if anyone will present a proof. If not, I may return to it. However, I've tested the numerical integration vs. the closed form for a total of 1000 evaluations for 10 different $a,, b, , x.$ The differences were 0 to within machine precision. The tests were over positive $a,, b, , x$ each from 0.1 to 6.5 by increments of 0.6.






share|cite|improve this answer




















  • Wow, I've looked at it numerically - and can't find any disagreements! :) Is your reasoning based on the residue theorem, or some other trick?
    – Can't integrate
    Sep 6 at 22:08






  • 1




    Briefly, I came up with another integral relationship that I started to estimate asymptotically. However, I recognized the asymptotic series could be summed in terms of the exp * erfc terms; hence the non-rigor. I'd be happy if someone would attempt a rigorous proof. One of the variables can be eliminated and probably a partial differential equation in two variables can be established that is satisfied by the integral form of J(a,b,x) and the closed form.
    – skbmoore
    Sep 6 at 22:44












up vote
2
down vote










up vote
2
down vote









Amazingly this integral can be solved in terms of well-known functions of mathematical physics. It is easy to see that
$$I(a,b,x):=int_0^infty fracp^5,sin(px)p^4+a^2,e^-b,p^2 dp =frac12 fracddb fracddx underbraceint_-infty^infty fracp^2,cos(px)p^4+a^2,e^-b,p^2 dp_:=J(a,b,x).$$
I won't do the derivatives, but present the formula for $J(a,b,x).$ Let $c=x/sqrt4b.$ Then
$$ J(a,b,x)=fracpi2sqrtb,e^-c^2,ReBig[frac1sqrti,a,b
Big( expbig( (sqrti,a,b - c)^2 big) , texterfcbig(sqrti,a,b - cbig) + $$
$$+ expbig( (sqrti,a,b + c)^2 big) , texterfcbig(sqrti,a,b + cbig) Big)Big] $$
The 'erfc' is the complimentary error function. My proof is long and not rigorous so we'll wait a few days to see if anyone will present a proof. If not, I may return to it. However, I've tested the numerical integration vs. the closed form for a total of 1000 evaluations for 10 different $a,, b, , x.$ The differences were 0 to within machine precision. The tests were over positive $a,, b, , x$ each from 0.1 to 6.5 by increments of 0.6.






share|cite|improve this answer












Amazingly this integral can be solved in terms of well-known functions of mathematical physics. It is easy to see that
$$I(a,b,x):=int_0^infty fracp^5,sin(px)p^4+a^2,e^-b,p^2 dp =frac12 fracddb fracddx underbraceint_-infty^infty fracp^2,cos(px)p^4+a^2,e^-b,p^2 dp_:=J(a,b,x).$$
I won't do the derivatives, but present the formula for $J(a,b,x).$ Let $c=x/sqrt4b.$ Then
$$ J(a,b,x)=fracpi2sqrtb,e^-c^2,ReBig[frac1sqrti,a,b
Big( expbig( (sqrti,a,b - c)^2 big) , texterfcbig(sqrti,a,b - cbig) + $$
$$+ expbig( (sqrti,a,b + c)^2 big) , texterfcbig(sqrti,a,b + cbig) Big)Big] $$
The 'erfc' is the complimentary error function. My proof is long and not rigorous so we'll wait a few days to see if anyone will present a proof. If not, I may return to it. However, I've tested the numerical integration vs. the closed form for a total of 1000 evaluations for 10 different $a,, b, , x.$ The differences were 0 to within machine precision. The tests were over positive $a,, b, , x$ each from 0.1 to 6.5 by increments of 0.6.







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answered Sep 6 at 21:30









skbmoore

1,52429




1,52429











  • Wow, I've looked at it numerically - and can't find any disagreements! :) Is your reasoning based on the residue theorem, or some other trick?
    – Can't integrate
    Sep 6 at 22:08






  • 1




    Briefly, I came up with another integral relationship that I started to estimate asymptotically. However, I recognized the asymptotic series could be summed in terms of the exp * erfc terms; hence the non-rigor. I'd be happy if someone would attempt a rigorous proof. One of the variables can be eliminated and probably a partial differential equation in two variables can be established that is satisfied by the integral form of J(a,b,x) and the closed form.
    – skbmoore
    Sep 6 at 22:44
















  • Wow, I've looked at it numerically - and can't find any disagreements! :) Is your reasoning based on the residue theorem, or some other trick?
    – Can't integrate
    Sep 6 at 22:08






  • 1




    Briefly, I came up with another integral relationship that I started to estimate asymptotically. However, I recognized the asymptotic series could be summed in terms of the exp * erfc terms; hence the non-rigor. I'd be happy if someone would attempt a rigorous proof. One of the variables can be eliminated and probably a partial differential equation in two variables can be established that is satisfied by the integral form of J(a,b,x) and the closed form.
    – skbmoore
    Sep 6 at 22:44















Wow, I've looked at it numerically - and can't find any disagreements! :) Is your reasoning based on the residue theorem, or some other trick?
– Can't integrate
Sep 6 at 22:08




Wow, I've looked at it numerically - and can't find any disagreements! :) Is your reasoning based on the residue theorem, or some other trick?
– Can't integrate
Sep 6 at 22:08




1




1




Briefly, I came up with another integral relationship that I started to estimate asymptotically. However, I recognized the asymptotic series could be summed in terms of the exp * erfc terms; hence the non-rigor. I'd be happy if someone would attempt a rigorous proof. One of the variables can be eliminated and probably a partial differential equation in two variables can be established that is satisfied by the integral form of J(a,b,x) and the closed form.
– skbmoore
Sep 6 at 22:44




Briefly, I came up with another integral relationship that I started to estimate asymptotically. However, I recognized the asymptotic series could be summed in terms of the exp * erfc terms; hence the non-rigor. I'd be happy if someone would attempt a rigorous proof. One of the variables can be eliminated and probably a partial differential equation in two variables can be established that is satisfied by the integral form of J(a,b,x) and the closed form.
– skbmoore
Sep 6 at 22:44

















 

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