a(n) = Sum_{k=0..n} binomial(n,k) * binomial(n^2,k^2).
A207140
a(n) = Sum_{k=0..n} binomial(n,k) * binomial(n^2,k^2).
Terms
- a(0) =1a(1) =2a(2) =10a(3) =407a(4) =56746a(5) =30771252a(6) =115106662819
External references
- oeis: A207140
A207140
a(n) = Sum_{k=0..n} binomial(n,k) * binomial(n^2,k^2).