Indices of centered triangular numbers (A005448) which are also centered pentagonal numbers (A005891).

A253470

Indices of centered triangular numbers (A005448) which are also centered pentagonal numbers (A005891).

Terms

    a(0) =1a(1) =5a(2) =36a(3) =280a(4) =2201a(5) =17325a(6) =136396a(7) =1073840a(8) =8454321a(9) =66560725a(10) =524031476a(11) =4125691080a(12) =32481497161a(13) =255726286205

External references