a(n) = Sum_{k=0..n} binomial(4*n+1,k) * binomial(2*n-k,n-k).
A385639
a(n) = Sum_{k=0..n} binomial(4*n+1,k) * binomial(2*n-k,n-k).
Terms
- a(0) =1a(1) =7a(2) =69a(3) =748a(4) =8485a(5) =98847a(6) =1171884a(7) =14066808a(8) =170421669a(9) =2079531685a(10) =25520363869a(11) =314653207128
External references
- oeis: A385639