a(n) = 5^n - 2*4^(n-1)*(n+4) + 3^(n-2)*(n^2+5*n+9).

Terms

a(0) =0a(1) =0a(2) =0a(3) =0a(4) =6a(5) =110a(6) =1220a(7) =10612a(8) =79786a(9) =544434a(10) =3468792a(11) =21012200a(12) =122500334a(13) =693324502a(14) =3833742796a(15) =20809676604a(16) =111288341970a(17) =588046458074