a(n) = Sum_{k=0..n} 2^k * binomial(n+2,k) * binomial(n+2,k+2).
A387337
a(n) = Sum_{k=0..n} 2^k * binomial(n+2,k) * binomial(n+2,k+2).
Terms
- a(0) =1a(1) =9a(2) =62a(3) =390a(4) =2355a(5) =13923a(6) =81340a(7) =471852a(8) =2725365a(9) =15698925a(10) =90278298a(11) =518620050a(12) =2977523367a(13) =17089401735a(14) =98073111800a(15) =562837648728
External references
- oeis: A387337