a(n) = Sum_{k=0..n} (-1)^k * binomial(2*n,k) * binomial(4*n,n-k).
A368467
a(n) = Sum_{k=0..n} (-1)^k * binomial(2*n,k) * binomial(4*n,n-k).
Terms
- a(0) =1a(1) =2a(2) =2a(3) =-16a(4) =-126a(5) =-498a(6) =-880a(7) =3432a(8) =37762a(9) =175916a(10) =411502a(11) =-710752a(12) =-12482928a(13) =-66911830a(14) =-190616760a(15) =70959984a(16) =4208145282a(17) =26042918836a(18) =86794308524a(19) =50521487200
External references
- oeis: A368467