a(n) = (5*n+10)(!^5)/10(!^5), related to A052562 ((5*n)(!^5) quintic, or 5-factorials).

A051691

a(n) = (5*n+10)(!^5)/10(!^5), related to A052562 ((5*n)(!^5) quintic, or 5-factorials).

Terms

    a(0) =1a(1) =15a(2) =300a(3) =7500a(4) =225000a(5) =7875000a(6) =315000000a(7) =14175000000a(8) =708750000000

External references