Heptagonal numbers (A000566) which are also centered triangular numbers (A005448).

A254676

Heptagonal numbers (A000566) which are also centered triangular numbers (A005448).

Terms

    a(0) =1a(1) =235a(2) =2839a(3) =902101a(4) =10906669a(5) =3465871039a(6) =41903418691

External references