a(n) = binomial(8*n, 2*n) / (6*n + 1).

A235536

a(n) = binomial(8*n, 2*n) / (6*n + 1).

Terms

    a(0) =1a(1) =4a(2) =140a(3) =7084a(4) =420732a(5) =27343888a(6) =1882933364a(7) =134993766600

External references