Coefficient of q^3 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)=(1,1).

A074083

Coefficient of q^3 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)=(1,1).

Terms

    a(0) =0a(1) =0a(2) =0a(3) =0a(4) =0a(5) =4a(6) =14a(7) =39a(8) =97a(9) =224a(10) =494a(11) =1051a(12) =2177a(13) =4412a(14) =8784a(15) =17228a(16) =33360a(17) =63886a(18) =121164a(19) =227833a(20) =425147a(21) =787916a(22) =1451198a(23) =2657821a(24) =4842727a(25) =8782230a(26) =15857426a(27) =28517864a(28) =51095760a(29) =91232520

External references