a(1) = 1, a(2) = 3, a(n+2) = 3*a(n+1) + (n + 1)*(n + 3)*a(n).
A142988
a(1) = 1, a(2) = 3, a(n+2) = 3*a(n+1) + (n + 1)*(n + 3)*a(n).
Terms
- a(0) =1a(1) =3a(2) =17a(3) =96a(4) =696a(5) =5448a(6) =49752a(7) =492480a(8) =5457600a(9) =65128320a(10) =850296960a(11) =11864240640a(12) =178442611200
External references
- oeis: A142988