a(0)=1, a(n) = Sum_{k=0..n} (binomial(n,k)^2 * binomial(n+k,k+1)^2)/n^2.
A074635
a(0)=1, a(n) = Sum_{k=0..n} (binomial(n,k)^2 * binomial(n+k,k+1)^2)/n^2.
Terms
- a(0) =1a(1) =2a(2) =14a(3) =162a(4) =2422a(5) =42366a(6) =824210a(7) =17315570a(8) =385569110a(9) =8985969258a(10) =217250577766
External references
- oeis: A074635