a(n) = Sum_{k=0..n} 3^k * binomial(n,k) * binomial(4*n+1,k).
A388050
a(n) = Sum_{k=0..n} 3^k * binomial(n,k) * binomial(4*n+1,k).
Terms
- a(0) =1a(1) =16a(2) =379a(3) =9946a(4) =273769a(5) =7747048a(6) =223222141a(7) =6514324144a(8) =191915445349
External references
- oeis: A388050