a(n) = Sum_{k=0..n} binomial(n+k-1,k) * binomial(2*n+2*k-1,n-k).
A378461
a(n) = Sum_{k=0..n} binomial(n+k-1,k) * binomial(2*n+2*k-1,n-k).
Terms
- a(0) =1a(1) =2a(2) =16a(3) =137a(4) =1216a(5) =11057a(6) =102229a(7) =956601a(8) =9032680a(9) =85893860a(10) =821402341a(11) =7891371303a(12) =76105710253a(13) =736364519399
External references
- oeis: A378461