a(n) = Sum_{k = 0..n} C(n,k)^6.

A069865

a(n) = Sum_{k = 0..n} C(n,k)^6.

Terms

    a(0) =1a(1) =2a(2) =66a(3) =1460a(4) =54850a(5) =2031252a(6) =86874564a(7) =3848298792a(8) =180295263810

External references