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[CALL] for challenging univariate symbolic integrals

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This is a call for univariate indefinite or definite exact integrals that cannot immediately computed in Mathematica and Wolfram Language. Submitted integrals will be collected for potential new event where they will be discussed and solved. You may refer to our previous event, which is showcased on the Wolfram Community post: https://community.wolfram.com/groups/-/m/t/2821053.
Do you have an integral that cannot be computed directly using Integrate ? Does the following apply to this integral?

Submission rules DOs

  • Univariate (terms in a single variable)
  • Exact (use only symbols, integers, or exact fractions).
  • Definite integrals (1, 2)
  • Indefinite Integrals (1, 2)
  • Keep comments directly related to the topics.

Submission rules DON'Ts

  • Don't submit those that Mathematica / Wolfram Language can do directly using Integrate[ ].
  • Don't submit numerical integrals (NIntegrate[ ])
  • Don't submit decimal approximate numbers in Integrate[ ].
  • Don't submit images, only copyable code.

If you have such an integral - please put it in a comment below!

Examples of submission formats

You can add a notebook with your integral:

You can post a formatted code:

Integrate[Gamma[s] z^-s, s]
POSTED BY: Oleg Marichev
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Looks like: $$\int_0^1 \frac{(1-x)^r (-2 x+(-2+x) \log (1-x))}{2 x \log ^2(1-x)} \, dx=1+r-r \log (1+r)-\frac{1}{2} \log (2 \pi (1+r))+\text{log$\Gamma $}(1+r)$$

 Integrate[((1 - x)^r (-2 x + (-2 + x) Log[1 - x]))/(2 x )*t (1 - x)^
   t, {t, 0, Infinity}, {x, 0, 1}, Assumptions -> {r >= 0, t >= 0}]

 (*1 + r - r Log[1 + r] - 1/2 Log[2 \[Pi] (1 + r)] + LogGamma[1 + r]*)

Regards M.I
POSTED BY: Mariusz Iwaniuk

I have a site of Table of Define integrals but you have to go through the whole list and see if Integrate can solve.

Attachments:
Define integrals.nb
POSTED BY: Mariusz Iwaniuk

Here is one:

POSTED BY: Ahmed Elbanna

Hi Oleg, since a long time I don't come to terms with all the orthogonality relations of polynomial families.

Just after the invention of the internet I found your books at Oxfords Blackwells,, ordered the four volumes and paid about 1000 GBP :-( The next days I found Mathenatica 2.0 in Hamburg for 50€ :-).

Here is my attempt with Jacobi polynomials (Gradshtey/Ryzhik 7.391) (Notebook attached)

Regards Roland

Attachments:
Integral submission.nb
POSTED BY: Roland Franzius

I have a site of Table of indefine integrals but you have to go through the whole list and see if Integrate can solve. Another site which can be very helpful.

My list attached below

Attachments:
111432973.nb
POSTED BY: Mariusz Iwaniuk

Another list for define integrals with attached files.

Attachments:
Table Całek Ozna...nb
Table Całek Ozna...nb
Table Całek Ozna...nb
POSTED BY: Mariusz Iwaniuk

I would be very interested in seeing a solution for this definite parameter integral:

Integrate[((1 - x)^r (-2 x + (-2 + x) Log[1 - x]))/(2 x Log[1 - x]^2), {x, 0, 1}, Assumptions -> r >= 0]
POSTED BY: Henrik Schachner

POSTED BY: Frank Iannarilli

2 another indefine integrals:

  Integrate[Exp[-a Sqrt[x]]*Exp[-a*Sqrt[ x - b]], x](* 1/2 b (E^(-a Sqrt[b]
        x) (1/x - (2 + 2 a Sqrt[b] x + a^2 b x^2)/(a^3 b^(3/2))) + 
     a Sqrt[b] ExpIntegralEi[-a Sqrt[b] x])*)

  Integrate[Gamma[a , x]^2/x^2, x](* -((2 E^-x x^(-1 + a) Gamma[a, x])/(-1 + a)) + Gamma[a, x]^2/(-1 + a) +
    Gamma[a, x]^2/((-1 + a) x) - (a Gamma[a, x]^2)/((-1 + a) x) + (
   2^(2 - 2 a) Gamma[-1 + 2 a, 2 x])/(-1 + a)*)
POSTED BY: Mariusz Iwaniuk

Another list for define integrals with attached files.

Examples from here.

Attachments:
Tintegrate integrals.nb
POSTED BY: Mariusz Iwaniuk

Nice trick ... :)
POSTED BY: Michal Kvasnicka

What a nice trick, indeed, I am impressed! Many thanks, Mariusz!

POSTED BY: Henrik Schachner

I opened a book about MellinTransform and tried a few examples:

    MellinTransform[(Sqrt[x^2 + a^2] + a)^\[Rho]/Sqrt[x^2 + a^2]*
     BesselJ[v, b*x], x, s, Method -> "Integrate", 
    Assumptions -> {b > 0, 
      Re[a] > 0, -Re[v] < Re[s] < 5/2 - Re[\[Rho]]}](*Can't Solve !*)

   MellinTransform[
    Exp[-\[Sigma] Sqrt[x] - \[Omega]*x] Hypergeometric1F1[a, 
      b, \[Omega]*x], x, s, Method -> "Integrate", 
    Assumptions -> {a > 0, b > 0, Re[\[Sigma]] > 0, 
      Re[s] > 0}](*Can't Solve !*)

   MellinTransform[
    1/(x + \[Sigma])^\[Rho] Hypergeometric2F1[a, b, 
      c, -\[Omega]*x], x, s, Method -> "Integrate", 
    Assumptions -> {Re[\[Rho]] > 0, Re[\[Sigma]] > 0, 
      Re[s] > 0}](*Can't Solve !*)
POSTED BY: Mariusz Iwaniuk

I opened another book about LaplaceTransform and tried a few examples:

      LaplaceTransform[BesselJ[v, a x] BesselI[v, b x], x, s, 
       Assumptions -> {Re[v] > 0, a > 0, b > 0}](*Can't Solve !*)

      LaplaceTransform[(1 - Exp[-x])^v* Erfc[ a (1 - Exp[-x])], x, s, 
       Assumptions -> {Re[v] > -1, a > 0}](*Can't Solve !*)

      LaplaceTransform[(1 - Exp[-x])^\[Mu]* Gamma[v, a*(1 - Exp[-x])], x, s,
        Assumptions -> {Re[\[Mu]] > -1, Re[v] > 0, a > 0}](*Can't Solve !*)

      LaplaceTransform[(x + a)^n*LegendreP[n, (x - a)/(x + a)], x, s, 
        Assumptions -> {Re[n] > 0, a > 0}](*Can't Solve !*)
POSTED BY: Mariusz Iwaniuk

I tried another very popular book with random integrals with Mathematica that can't solve:

Attachments:
Define Integrals.nb
POSTED BY: Mariusz Iwaniuk

It should be nice to generalize Integrate function to be able to solve this directly:

Integrate[((1 - x)^r (-2 x + (-2 + x) Log[1 - x]))/(2 x Log[1 - x]^2), {x, 0, 1}, Assumptions -> r >= 0]

using (in this specific case) the following identity:

1/Log[1 - x]^2 = Integrate[t (1 - x)^t, {t, 0, Infinity}] if Re[Log[1 - x]] < 0

like

Integrate[((1 - x)^r (-2 x + (-2 + x) Log[1 - x]))/(2 x)*
  t (1 - x)^t, {t, 0, Infinity}, {x, 0, 1}, Assumptions -> r >= 0]
POSTED BY: Michal Kvasnicka
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