a(n) = Sum_{k = 0..n-1} binomial(n-1,k)^2*binomial(n+k,k).
A361717
a(n) = Sum_{k = 0..n-1} binomial(n-1,k)^2*binomial(n+k,k).
Terms
- a(0) =0a(1) =1a(2) =4a(3) =27a(4) =216a(5) =1875a(6) =17088a(7) =160867a(8) =1549936a(9) =15195843a(10) =151017780a(11) =1517232189a(12) =15379549056a(13) =157058738343
External references
- oeis: A361717