a(n) = Sum_{k=0..n} binomial(4*n+2,k) * binomial(4*n-k,n-k).

A386845

a(n) = Sum_{k=0..n} binomial(4*n+2,k) * binomial(4*n-k,n-k).

Terms

    a(0) =1a(1) =10a(2) =143a(3) =2264a(4) =37601a(5) =642086a(6) =11165395a(7) =196658228a(8) =3496849349a(9) =62636490818

External references