a(n) = Sum_{k=0..n} 2^(n-k) * binomial(n,k) * binomial(3*n+1,k).
A388130
a(n) = Sum_{k=0..n} 2^(n-k) * binomial(n,k) * binomial(3*n+1,k).
Terms
- a(0) =1a(1) =6a(2) =53a(3) =518a(4) =5307a(5) =55880a(6) =599020a(7) =6502998a(8) =71263271a(9) =786630134a(10) =8733431973a(11) =97419158248
External references
- oeis: A388130