a(0) = 0, a(n) = 2^binomial(n,2) - 2^(n - 1).

A326289

a(0) = 0, a(n) = 2^binomial(n,2) - 2^(n - 1).

Terms

    a(0) =0a(1) =0a(2) =0a(3) =4a(4) =56a(5) =1008a(6) =32736a(7) =2097088a(8) =268435328a(9) =68719476480

External references