a(n) = Sum_{k=0..2n-2} T(n,k) * T(n,k+2), with T given by A025177.
A027259
a(n) = Sum_{k=0..2n-2} T(n,k) * T(n,k+2), with T given by A025177.
Terms
- a(0) =5a(1) =40a(2) =342a(3) =2941a(4) =25333a(5) =218659a(6) =1891683a(7) =16403283a(8) =142548639a(9) =1241293314a(10) =10829045472a(11) =94632148659a(12) =828235716571
External references
- oeis: A027259