a(n) = Sum_{k=0..n-1} T(n,k) * T(n,k+1), with T given by A026670.
A026982
a(n) = Sum_{k=0..n-1} T(n,k) * T(n,k+1), with T given by A026670.
Terms
- a(0) =1a(1) =6a(2) =24a(3) =120a(4) =460a(5) =2214a(6) =8475a(7) =40164a(8) =154235a(9) =724742a(10) =2792579a(11) =13050280a(12) =50432693a(13) =234766510a(14) =909442512a(15) =4221139640a(16) =16384219216a(17) =75873259406a(18) =294977735364
External references
- oeis: A026982