For n, p∈\(\mathbb{N}\) -{1}, the coefficient of x3 in \(\rm\frac{(1-x)^{-1/p}}{(1-x)^n}\) =
1
\(\rm\frac{(np+1)(np+p+1)(np+2p+1)}{p^3\times3!}\)
2
\(\rm\frac{(np+1)(np+p)(np+2p)}{3!p^3}\)
3
\(\rm\frac{(np+p)(np+2p)(np+3p)}{3!p^3}\)
4
\(\rm\frac{(np+1)(np+2)(np+3)}{3!p^3}\)