a(n) = a(n - 1)*a(n - 2) + a(n - 2)*a(n - 3) + a(n - 1)*a(n - 3).

A121810

a(n) = a(n - 1)*a(n - 2) + a(n - 2)*a(n - 3) + a(n - 1)*a(n - 3).

Terms

    a(0) =1a(1) =1a(2) =0a(3) =1a(4) =1a(5) =1a(6) =3a(7) =7a(8) =31a(9) =331a(10) =12795a(11) =4642051a(12) =60935796571

External references