a(n) = (-1)^n + 3 * Sum_{k=0..n-1} a(k) * a(n-k-1).
A337169
a(n) = (-1)^n + 3 * Sum_{k=0..n-1} a(k) * a(n-k-1).
Terms
- a(0) =1a(1) =2a(2) =13a(3) =89a(4) =691a(5) =5720a(6) =49555a(7) =443630a(8) =4071595a(9) =38105342a(10) =362271823a(11) =3488988101a(12) =33967656469a(13) =333752559392
External references
- oeis: A337169