Answer
See below
Work Step by Step
Let $\Gamma (p)$ denote the gamma function.
Obtain: $p \Gamma (p)=\Gamma (p+1)$
then
$\Gamma (p+k+1)=(p+k)\Gamma (p+k)\\
=(p+k)\Gamma (p+k-1+1)\\
=(p+k)\Gamma (p+k-1+1)\\
=(p+k)(p+k-1)\Gamma (p+k-1)\\
=(p+k)(p+k-1)\Gamma (p+k-2+1)\\
=(p+k)(p+k-1)(p+k-2)\Gamma (p+k-2)\\
=(p+k)(p+k-1)(p+k-2)...(p+3)\Gamma (p+3)\\
=(p+k)(p+k-1)(p+k-2)... (p+3)(p+2)\Gamma (p+2)\\
=(p+k)(p+k-1)(p+k-2)...(p+3)(p+2)\Gamma (p+1+1)\\
=(p+k)(p+k-1)(p+k-2)...(p+3)(p+2)(p+1)\Gamma (p+1)$