Centered heptagonal numbers (A069099) which are also centered pentagonal numbers (A005891).

A253622

Centered heptagonal numbers (A069099) which are also centered pentagonal numbers (A005891).

Terms

    a(0) =1a(1) =106a(2) =15016a(3) =2132131a(4) =302747551a(5) =42988020076

External references