a(n) = Sum_{k=0..n} (-1)^k * binomial(5*n-k+4,n-k).
A390593
a(n) = Sum_{k=0..n} (-1)^k * binomial(5*n-k+4,n-k).
Terms
- a(0) =1a(1) =8a(2) =79a(3) =832a(4) =9066a(5) =100904a(6) =1139440a(7) =13003264a(8) =149587819a(9) =1731728848a(10) =20150025842a(11) =235447974208
External references
- oeis: A390593