Clausen's identity
Another identity ascribed to Clausen which involves the Hypergeometric Function and the Generalized Hypergeometric Function is given by
See also Generalized Hypergeometric Function, Hypergeometric Function
References
Petkovsek, M.; Wilf, H. S.; and Zeilberger, D. A=B. Wellesley, MA: A. K. Peters, pp. 43 and 127, 1996.