Coefficient of q^1 in nu(n), where nu(0)=1, nu(1)=b and, for n >= 2, nu(n) = b*nu(n-1) + lambda*(1 + q + q^2 + ... + q^(n-2))*nu(n-2) with (b,lambda)=(2,2).

A074358

Coefficient of q^1 in nu(n), where nu(0)=1, nu(1)=b and, for n >= 2, nu(n) = b*nu(n-1) + lambda*(1 + q + q^2 + ... + q^(n-2))*nu(n-2) with (b,lambda)=(2,2).

Terms

    a(0) =0a(1) =0a(2) =0a(3) =4a(4) =20a(5) =80a(6) =288a(7) =976a(8) =3184a(9) =10112a(10) =31488a(11) =96576a(12) =292672a(13) =878336a(14) =2614784a(15) =7731456a(16) =22728448a(17) =66482176a(18) =193617920a(19) =561718272a(20) =1624101888a(21) =4681535488a(22) =13457924096a(23) =38592008192a(24) =110419341312a(25) =315287830528a(26) =898583560192

External references