a(n) = Sum_{k=0..n} (-1)^(n-k) * binomial(n,k) * binomial(5*k,k) / (4*k + 1).

A346665

a(n) = Sum_{k=0..n} (-1)^(n-k) * binomial(n,k) * binomial(5*k,k) / (4*k + 1).

Terms

    a(0) =1a(1) =0a(2) =4a(3) =22a(4) =172a(5) =1409a(6) =12216a(7) =109904a(8) =1016876a(9) =9614584a(10) =92490261a(11) =902364918a(12) =8907507708a(13) =88802649446a(14) =892833960460

External references