a(n) = Sum_{k=0..2n-1} T(n,k) * T(n,k+1), with T given by A026519.
A027263
a(n) = Sum_{k=0..2n-1} T(n,k) * T(n,k+1), with T given by A026519.
Terms
- a(0) =2a(1) =6a(2) =52a(3) =180a(4) =1516a(5) =5502a(6) =46936a(7) =174456a(8) =1504432a(9) =5673140a(10) =49288856a(11) =187675644a(12) =1639174304a(13) =6284986554a(14) =55108565584a(15) =212408191568
External references
- oeis: A027263