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2 votes
1 answer
188 views

Incomplete integral of confluent hypergeometric function

I would like to prove the following: if $a,b,c > 0$, $0<x<1$, $y>0$, then, $$ \frac{1}{\Gamma(b)}\int_0^{\infty} s^{b-1} e^{-s} \,\mbox{$ {}_1\mathrm{F}_1 (a\,; c\,; x s + y\hspace{1pt})$}\...
japalmer's user avatar
  • 391
1 vote
1 answer
197 views

Derivation of indefinite integral involving hypergeometric function

I am doing a project on projectile motion and I ended up with this integral: $$\int \frac{m \left(g - \left(\frac{1}{e^t - g^{\frac{m}{c}}}\right)^{\frac{m}{c}}\right)}{c} \, dt$$ where $g, c,$ and $m$...
Leo McIntyre's user avatar
1 vote
0 answers
197 views

Infinite series involving generalised hypergeometric functions

I've recently stumbled into hypergeometric functions while trying to evaluate the integral: $$ \int \exp \big( x^2 + bx + c \big) {\rm erf} ( x ) \operatorname{d\!}x $$ Essentially, working from an ...
Mat's user avatar
  • 41
0 votes
1 answer
128 views

Generalization of identity for terminating hypergeometric function

Let ${}_2F_1(a,b;c;z)$ be the ordinary hypergeometric function for $z \in \mathbb{C}$ \begin{equation} {}_2F_1(a,b;c;z) = \sum_{k=0}^{\infty} \frac{z^k}{k!} \frac{(a)_{k} (b)_k}{(c)_k}\,, \end{...
eriugena's user avatar
  • 679
2 votes
0 answers
81 views

Uniform bound on a certain family of hypergeometric functions

We have the following problem, which we can't solve. Let $a \in \mathbb{C}$ be fixed, with real part $1/2$ and imaginary part $\neq 0$. We consider parameters $n \in \mathbb{Z}$ and $k \in \mathbb{Z}_{...
Sasha's user avatar
  • 5,562
1 vote
1 answer
173 views

Higher-order asymptotics of generalized hypergeometric function

I have a question about higher-order asymptotics of generalized hypergeometric functions. According to https://dlmf.nist.gov/15.4 the following is well known: $$ _2F_1(a,b;a+b;z)\sim -\frac{\Gamma(a+b)...
Predrag Punosevac's user avatar
11 votes
1 answer
566 views

Integral representation of product of two Whittaker functions

Does anyone know anything about the following formula involving special functions: $$\begin{multline*} W_{\kappa,\mu}(z)W_{\lambda,\mu}(w)=\frac{e^{-(z+w)/2}(zw)^{\mu+1/2}}{\Gamma(1-\kappa-\lambda)}\...
Y.Okuyama's user avatar
  • 373
3 votes
2 answers
266 views

Integral expressions for Bessel-like power series

I'm interested in power series of form $$f(z)=\sum_{k=0}^\infty \frac{z^k}{(k!)^\alpha}.$$ When $\alpha=1$, this becomes $\exp(z)$. For $\alpha=2$ this is a Bessel function and for larger integer $\...
MCH's user avatar
  • 1,324
2 votes
1 answer
478 views

Correction terms in the asymptotic expansion of hypergeometric function

I am interested in obtaining the asymptotic expansion of $r(\rho)$ (which is the inverse of $\rho$ below), $$\rho=\frac{2b}{1-q}\left(1-\left(\frac br\right)^{1-q}\right)^{1/2}\left(_2F_1\left(\frac{1}...
user583893's user avatar
3 votes
1 answer
599 views

Compute Confluent Hypergeometric Function 1F1

I am attempting to compute the (Kummer's) confluent hypergeometric function (see also here) \begin{align} M\left(\frac{n}{2}, n +\frac{3}{2}, -z\right) = {}_1F_1\left(\frac{n}{2};n +\frac{3}{2};-z\...
sethaxen's user avatar
3 votes
0 answers
106 views

Does the Riemann characterization of the hypergeometric function have a q-analog?

This question is inspired by another recent one here, Characterization of the hypergeometric function. The latter is about the classical result of Riemann characterizing the hypergeometric functions ...
მამუკა ჯიბლაძე's user avatar
4 votes
1 answer
211 views

Perform an integration over the unit interval of a two-parameter expression involving a Gauss hypergeometric function

In a quantum-information-theoretic context, I've encountered the problem of integrating over $r \in [0,1]$, the function \begin{equation} r^{2 d-1} \, _2F_1\left(-\frac{d}{2},\frac{d}{2};\frac{d+2}{2}...
Paul B. Slater's user avatar
6 votes
1 answer
363 views

Double Series involving Gamma function

Does anyone have any ideas on howto verify $$\sum_{n,m=0}^\infty \frac{\Gamma(n+m+3x)}{\Gamma(n+1+x)\Gamma(m+1+x)}\cdot \frac{1}{3^{n+m+3x-1}} = \Gamma(x)$$ for $x>0$? I posted this question also ...
maliesen's user avatar
  • 284
5 votes
0 answers
388 views

Is a basic hypergeometric function ${}_2\phi_1(a, b; c; q, z)$ a meromorphic function in $z$?

Here a basic hypergeometric function is the analytic continuation of the basic hypergeometric series (or called the $q$-hypergeometric series) $$ {}_2\phi_1(a, b; c; q, z) = \sum^{\infty}_{n = 0} \...
Dong Wang's user avatar
  • 123
4 votes
2 answers
522 views

Analytic continuation of $_4F_3(1)$

The Gauss theorem $${_2F_1}(a,b;c;1)=\frac{\Gamma(c-a)\Gamma(c-b)}{\Gamma(c)\Gamma(c-a-b)}$$ allows to compute the analytic continuation of ${_2F_1}(a,b;c;1)$ for $a+b>c$ when the series ...
Dmitri's user avatar
  • 41
40 votes
1 answer
2k views

Curious $q$-analogues

Consider the Fibonacci polynomials $$F_n (x) = \sum_{j = 0}^{\left\lfloor {n/2} \right\rfloor }\binom{n-j}{j} x^{n - 2j} $$ and the Lucas polynomials $$L_n (x) = \sum_{j = 0}^{\left\lfloor {n/2} \...
Johann Cigler's user avatar