a(n) = n! * Sum_{k=0..n} binomial(2*n, 2*k) / binomial(n,k).
A182525
a(n) = n! * Sum_{k=0..n} binomial(2*n, 2*k) / binomial(n,k).
Terms
- a(0) =1a(1) =2a(2) =10a(3) =72a(4) =664a(5) =7440a(6) =98064a(7) =1486464a(8) =25476480a(9) =487192320a(10) =10284768000a(11) =237574149120
External references
- oeis: A182525