a(n) = Sum_{k=0..n} binomial(n,k) * binomial(n+3*k,k).
A388534
a(n) = Sum_{k=0..n} binomial(n,k) * binomial(n+3*k,k).
Terms
- a(0) =1a(1) =5a(2) =39a(3) =347a(4) =3263a(5) =31635a(6) =312735a(7) =3133723a(8) =31715191a(9) =323436371a(10) =3318437029a(11) =34214183085a(12) =354192729971
External references
- oeis: A388534