a(n) = Sum_{k=0..n} (-1)^k * (k+1) * binomial(4*n-3*k+1,n-k)/(4*n-3*k+1).
A387982
a(n) = Sum_{k=0..n} (-1)^k * (k+1) * binomial(4*n-3*k+1,n-k)/(4*n-3*k+1).
Terms
- a(0) =1a(1) =0a(2) =3a(3) =15a(4) =100a(5) =702a(6) =5187a(7) =39697a(8) =312013a(9) =2503839a(10) =20429974a(11) =168985397a(12) =1413733042a(13) =11941669508a(14) =101705923521a(15) =872436699540
External references
- oeis: A387982