a(5) = 5, a(6) = 1170, for n >= 7, a(n) = n!*(4*n^3 - 30*n^2 + 40*n + 3)/24.
A034864
a(5) = 5, a(6) = 1170, for n >= 7, a(n) = n!*(4*n^3 - 30*n^2 + 40*n + 3)/24.
Terms
- a(0) =5a(1) =1170a(2) =38850a(3) =757680a(4) =12836880a(5) =212133600a(6) =3554258400a(7) =61372080000
External references
- oeis: A034864