a(n) = Sum_{k=0..n} binomial(n,k) * binomial(n+3*k-1,3*k).
A378378
a(n) = Sum_{k=0..n} binomial(n,k) * binomial(n+3*k-1,3*k).
Terms
- a(0) =1a(1) =2a(2) =16a(3) =170a(4) =1920a(5) =22402a(6) =266800a(7) =3222634a(8) =39328768a(9) =483752258a(10) =5987236816a(11) =74474238698a(12) =930212870784
External references
- oeis: A378378