Finite–classical correspondence for Euler sums
Establish, for every weight \(w\), the conjectured isomorphism between the vector space generated by finite Euler sums of weight \(w\) and the quotient of the vector space generated by classical Euler sums of weight \(w\) by \(\zeta(2)ES_{w-2}\), with the map sending each finite Euler sum to its symmetric regularized classical counterpart modulo \(\zeta(2)\).
References
The author proposed the following key conjecture (see Conjecture~8.6.9) by extending the above conjecture of Kakeko and Zagier from MZVs to Euler sums. For any $w\inN$, let $FES_{w}$ (resp.\ $ES_w$) be the $Q$-vector space generated by all finite Euler sums (resp.\ Euler sums) of weight $w$. Then, there is an isomorphism:
— Effective Euler Sums
(2609.09260 - Zhao, 8 Sep 2026) in Conjecture 1.1, subsection “Finite Euler sum and the key conjecture”