a(n) = Sum_{k=0..n} binomial(n,k)^2 * abs(Stirling1(2*k,k)) * abs(Stirling1(2*n-2*k,n-k)).
A384495
a(n) = Sum_{k=0..n} binomial(n,k)^2 * abs(Stirling1(2*k,k)) * abs(Stirling1(2*n-2*k,n-k)).
Terms
- a(0) =1a(1) =2a(2) =26a(3) =648a(4) =25094a(5) =1372100a(6) =99827020a(7) =9233563136
External references
- oeis: A384495