a(n) = 2^(4*n-1) - 2^(2*n-1)*binomial(2*n,n).

A055787

a(n) = 2^(4*n-1) - 2^(2*n-1)*binomial(2*n,n).

Terms

    a(0) =0a(1) =4a(2) =80a(3) =1408a(4) =23808a(5) =395264a(6) =6496256a(7) =106102784a(8) =1725759488a(9) =27987017728a(10) =452890460160

External references