a(n) = Sum_{k=0..n} 2^(n-k) * binomial(4*n,k).
A385498
a(n) = Sum_{k=0..n} 2^(n-k) * binomial(4*n,k).
Terms
- a(0) =1a(1) =6a(2) =48a(3) =408a(4) =3564a(5) =31626a(6) =283548a(7) =2560872a(8) =23255964a(9) =212101176a(10) =1941110628a(11) =17815257048a(12) =163896843300
External references
- oeis: A385498