Heptagonal numbers (A000566) that are also centered hexagonal numbers (A003215).

A254966

Heptagonal numbers (A000566) that are also centered hexagonal numbers (A003215).

Terms

    a(0) =1a(1) =7a(2) =469a(3) =3367a(4) =226051a(5) =1622881a(6) =108956107a(7) =782225269a(8) =52516617517a(9) =377030956771

External references