A class of relations among multiple zeta values

We prove a new class of relations among multiple zeta values (MZV's) which contains Ohno's relation. We also give the formula for the maximal number of independent MZV's of fixed weight, under our new relations. To derive our formula for MZV's we consider the Newton series whose values at non-negative integers are finite multiple harmonic sums.Comment: 36 pages, presentation improved, to appear in Journal of Number Theor

Optimization Algorithms Based on Renormalization Group

Global changes of states are of crucial importance in optimization algorithms. We review some heuristic algorithms in which global updates are realized by a sort of real-space renormalization group transformation. Emphasis is on the relationship between the structure of low-energy excitations and ``block-spins'' appearing in the algorithms. We also discuss the implication of existence of a finite-temperature phase transition on the computational complexity of the ground-state problem.Comment: 7 pages, 2 figure