where is a binomial coefficient and is a gamma function.
Dixon's Identity
See also
Dixon's TheoremExplore with Wolfram|Alpha
References
Koepf, W. Hypergeometric Summation: An Algorithmic Approach to Summation and Special Function Identities. Braunschweig, Germany: Vieweg, pp. 11 and 18-19, 1998.Referenced on Wolfram|Alpha
Dixon's IdentityCite this as:
Weisstein, Eric W. "Dixon's Identity." From MathWorld--A Wolfram Web Resource. https://mathworld.wolfram.com/DixonsIdentity.html