a(n) = Sum_{k = 0..n} (-1)^(n+k) * binomial(n,k)*binomial(n+k-1,n)* binomial(3*n+k-1,n).
A365028
a(n) = Sum_{k = 0..n} (-1)^(n+k) * binomial(n,k)*binomial(n+k-1,n)* binomial(3*n+k-1,n).
Terms
- a(0) =1a(1) =3a(2) =33a(3) =462a(4) =7185a(5) =118503a(6) =2029650a(7) =35690868a(8) =639948177a(9) =11647493715a(10) =214523842533
External references
- oeis: A365028