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

A253621

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

Terms

    a(0) =1a(1) =6a(2) =66a(3) =781a(4) =9301a(5) =110826a(6) =1320606a(7) =15736441a(8) =187516681a(9) =2234463726a(10) =26626048026a(11) =317278112581

External references