a(n) = Sum_{k=0..2n-2} T(n,k) * T(n,k+2), with T given by A026519.
A027264
a(n) = Sum_{k=0..2n-2} T(n,k) * T(n,k+2), with T given by A026519.
Terms
- a(0) =5a(1) =40a(2) =150a(3) =1279a(4) =4797a(5) =41462a(6) =156900a(7) =1365014a(8) =5205950a(9) =45501743a(10) =174609162a(11) =1531614109a(12) =5906040623a(13) =51952990090a(14) =201114700568
External references
- oeis: A027264