Fast formulas for the Hurwitz values $ζ(2,a)$ and $ζ(3,a)$ (2504.01975v2)

Abstract: We prove two fast formulas for the Hurwitz values $\zeta(2,a)$ and $\zeta(3,a)$ respectively with the help of the WZ method. In them $(a)n$ denotes the rising factorial or Pochhammer's symbol defined by $(a)_0=1$ and $(a)_n=a(a+1)\cdots(a+n-1)$ for positive integers $n$. The Huwitz $\zeta$ function is defined by $\zeta(s,a)=\zeta(0,s,a)=\sum{k=0}^{\infty} (k+a)^{-s}$.