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{\bf Michael E. Hoffman}
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{\bf A Character on the Quasi-Symmetric Functions coming from Multiple Zeta Values}
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We define a homomorphism $\zeta$ from the algebra of quasi-symmetric
functions to the reals which involves the Euler constant and multiple
zeta values. Besides advancing the study of multiple zeta values, the
homomorphism $\zeta$ appears in connection with two Hirzebruch genera of
almost complex manifolds: the $\Gamma$-genus (related to mirror symmetry)
and the $\hat{\Gamma}$-genus (related to an $S^1$-equivariant Euler
class). We decompose $\zeta$ into its even and odd factors in the sense
of Aguiar, Bergeron, and Sottille, and demonstrate the usefulness of
this decomposition in computing $\zeta$ on the subalgebra of symmetric
functions (which suffices for computations of the $\Gamma$- and
$\hat{\Gamma}$-genera).
\bye