a(n) = Sum_{k=0..n} binomial(n+k-1,k) * binomial(n+2*k-1,n-k).
A378566
a(n) = Sum_{k=0..n} binomial(n+k-1,k) * binomial(n+2*k-1,n-k).
Terms
- a(0) =1a(1) =1a(2) =9a(3) =64a(4) =465a(5) =3456a(6) =26082a(7) =199060a(8) =1532313a(9) =11875015a(10) =92528414a(11) =724187982a(12) =5689127886a(13) =44834549501a(14) =354289977750
External references
- oeis: A378566