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1 vote
2 answers
129 views

Calculation for negative integer order Associated Legendre Function

I am currently engaging with the following hypergeometric function as a result of attempting to find a solution for this probability problem for $n$ number of dice: $$_2F_1\left (\frac{n+k}{2}, \frac{...
Lee Davis-Thalbourne's user avatar
0 votes
0 answers
78 views

"Legendre-type" integrals involving $\frac{dt}{\sqrt{t^2-2t\cos(\theta)+1}}$

Summing Legendre polynomials $P_{l}(\cos\theta)$ often leads to expressions containing $\frac{1}{\sqrt{t^2-2t\cos\theta+1}}$, as this is the generating function for the Legendre polynomials. I want to ...
Luke's user avatar
  • 203
2 votes
0 answers
235 views

Integral of associated Legendre polynomials over the unit interval

I am looking for a closed-form expression for the integral of the associated Legendre polynomial $P_l^m$ over the unit interval ($l \ge m$ non-negative integers), $$ I_l^m = \int_{0}^{1} P_l^m(x) \, ...
ntessore's user avatar
2 votes
1 answer
65 views

How to merge odd series and even series of hypergeometric function of Legendre polynomials into one hypergeometric function?

On the Wolfram MathWorld page of Legendre Differential Equation, Legendre polynomials are represented as $$ P_l(x) = c_n \begin{cases}\begin{align*} &_2F_1\left(-\frac{1}{2}(l), \frac{1}{2}(l + 1);...
gyro's user avatar
  • 314
6 votes
1 answer
198 views

Fourier Legendre expansion of Beta kernel $x^a (1-x)^b$

Preliminaries. I have difficulty computing FL expansion of Beta kernel $f_{a,b}(x)=x^a (1-x)^b$ where $4a, 4b \in \mathbb{Z}$. Here are two important examples: $a=s-1,b=0: x^{s-1}=\sum_{n=0}^\infty \...
Infiniticism's user avatar
  • 8,654
6 votes
2 answers
419 views

Proof for a combinatorial identity

I have the following formula, which I believe it's true since it works in Mathematica for all values of $N$ I have tried, but I don't know how to prove it: $$\sum_{q=0}^{N} {N \choose q}^2 x^{q} = \...
MBolin's user avatar
  • 759
5 votes
1 answer
255 views

General method of evaluating $\small\sum_{n\geq 0}\left(\frac{4^n}{(2n+1)\binom{2n}{n}}\right)^2\frac{1}{n+k}$

Question: $ \mbox{How can we evaluate}\quad \sum_{n \geq 0}\left[{4^{n} \over \left(\, 2n + 1\,\right) \binom{2n}{n}}\right]^{2}{1 \over n + k}\quad \mbox{for general $k$ ?.} $ General methodology ...
Infiniticism's user avatar
  • 8,654
4 votes
1 answer
259 views

Evaluate hypergeometric $_6F_5\left(\{\frac12\}_6;1,\{\frac32\}_4;1\right)$

Background: I'm searching for $_pF_q$ representations for MZVs. In related article On the interplay between hypergeometric series, Fourier-Legendre expansions and Euler sums by M. Cantarini and J. D’...
Infiniticism's user avatar
  • 8,654
10 votes
1 answer
578 views

Evaluate $\int_0^1 x^{a-1}(1-x)^{b-1}\operatorname{Li}_3(x) \, dx$

Define $\small f(a,b)=\frac1{B(a,b)}\int_0^1 x^{a-1}(1-x)^{b-1} \text{Li}_3(x) \, dx$$ $$=\frac a{a+b}{}_5F_4(1,1,1,1,a+1;2,2,2,1+a+b;1)$ Where $a>-1$ and $b>0$. $1$. By using contour ...
Kemono Chen's user avatar
  • 8,679
1 vote
1 answer
140 views

How to convert a hypergeom function to the Legendre function?

Anyone can help me to convert the following maple pdsolve expressed by the hypergeom function to the $LegendreP(n,b,x)$ or $Q$ function? \begin{equation} dsolve\Big( (1-x^2)\cdot \frac{d^2 y(x)}{dx^...
Ahmad's user avatar
  • 55
25 votes
3 answers
976 views

An elementary proof of $\int_{0}^{1}\frac{\arctan x}{\sqrt{x(1-x^2)}}\,dx = \frac{1}{32}\sqrt{2\pi}\,\Gamma\left(\tfrac{1}{4}\right)^2$

When playing with the complete elliptic integral of the first kind and its Fourier-Legendre expansion, I discovered that a consequence of $\sum_{n\geq 0}\binom{2n}{n}^2\frac{1}{16^n(4n+1)}=\frac{1}{16\...
Jack D'Aurizio's user avatar
1 vote
0 answers
514 views

Hypergeometric relation from Legendre functions

When writing the relation for the Legendre polynomials $$ P^{-\mu}_{\nu}(z) = (-1)^{\mu} {\Gamma(\nu-\mu+1) \over \Gamma(\nu+\mu+1)} P^{\mu}_{\nu}(z) $$ in the Gauss hypergeometric representation, we ...
ABarr's user avatar
  • 161
2 votes
2 answers
502 views

Associated Legendre function hypergeometric representation; case of integer l, m

The associated Legendre functions for general l, m (i.e, l and m are not in general integers) can be written in terms of the hypergeometric function $_2F_1(a,b,c;x)$ thus: $$P^m_l(x) = (\frac{x+1}{x-1}...
CrossProduct's user avatar
3 votes
1 answer
655 views

Identity relating hypergeometric function and Legendre polynomial

In my notes I have written down the following relation: $_2F_1(a,a+\frac{1}{2};c;z)=2^{c-1}z^{(1-c)/2}(1-z)^{-a+(c-1)/2}L_{2a-c}^{1-c}\big(\frac{1}{\sqrt{1-z}}\big)\ ,$ where $_2F_1(a,b;c;z)$ is the ...
jorgen's user avatar
  • 916