A generalization of Wilf's formula

抄録

A remarkable infinite product formula was recently posed as a problem by Wilf [6]. Subsequently, Choi and Seo [2] proved Wilf's formula as well as three other analogous product formulas. The main object of this sequel to these earlier works is to present several general infinite product formulas which include, as their special cases, the aforementioned product formulas of Wilf [6] and Choi and Seo [2]. Some other related results, involving the Riemann Zeta function, are also considered briefly.