a(n) = Sum_{k = 0..n-1} binomial(n,k)*binomial(n-1,k)*binomial(n+k,k)*binomial(n-1+k,k).
A352653
a(n) = Sum_{k = 0..n-1} binomial(n,k)*binomial(n-1,k)*binomial(n+k,k)*binomial(n-1+k,k).
Terms
- a(0) =0a(1) =1a(2) =13a(3) =253a(4) =5741a(5) =142001a(6) =3713305a(7) =100961365a(8) =2825369965a(9) =80843126905
External references
- oeis: A352653