a(n) = Sum_{k=0..n} 4^(n-k) * binomial(n,k) * binomial(n+4,k).
A388414
a(n) = Sum_{k=0..n} 4^(n-k) * binomial(n,k) * binomial(n+4,k).
Terms
- a(0) =1a(1) =9a(2) =79a(3) =687a(4) =5958a(5) =51670a(6) =448594a(7) =3900594a(8) =33972207a(9) =296364743a(10) =2589446313a(11) =22658037737a(12) =198530526492
External references
- oeis: A388414