a(n) = Sum_{k=0..n+1} T(n,k) * T(n,k+1), with T given by A026323.
A027309
a(n) = Sum_{k=0..n+1} T(n,k) * T(n,k+1), with T given by A026323.
Terms
- a(0) =2a(1) =16a(2) =123a(3) =956a(4) =7519a(5) =59742a(6) =478869a(7) =3868104a(8) =31458348a(9) =257396972a(10) =2117494621a(11) =17504651148a(12) =145341743066
External references
- oeis: A027309