a(n) = Sum_{k=0..n} binomial(4*n,4*k).

A070775

a(n) = Sum_{k=0..n} binomial(4*n,4*k).

Terms

    a(0) =1a(1) =2a(2) =72a(3) =992a(4) =16512a(5) =261632a(6) =4196352a(7) =67100672a(8) =1073774592a(9) =17179738112a(10) =274878431232

External references