a(n) = Sum_{k=0..n} 2^(n-k) * binomial(4*n+1,k).
A385605
a(n) = Sum_{k=0..n} 2^(n-k) * binomial(4*n+1,k).
Terms
- a(0) =1a(1) =7a(2) =58a(3) =502a(4) =4436a(5) =39687a(6) =358024a(7) =3249288a(8) =29624796a(9) =271080124a(10) =2487835678a(11) =22888216006a(12) =211010997716
External references
- oeis: A385605