a(n) = Sum_{k=0..n-1} T(n,k) * T(n,k+1), with T given by A026374.
A026947
a(n) = Sum_{k=0..n-1} T(n,k) * T(n,k+1), with T given by A026374.
Terms
- a(0) =1a(1) =6a(2) =24a(3) =144a(4) =541a(5) =3258a(6) =12275a(7) =74280a(8) =282003a(9) =1713690a(10) =6549906a(11) =39938616a(12) =153481299a(13) =938430990a(14) =3622111560a(15) =22195961280a(16) =85975792075a(17) =527816696850
External references
- oeis: A026947