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Annihilating polynomials for quadratic forms and Stirling numbers of the second kind

Stefan A. G. De Wannemacker
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Abstract

We present a set of generators of the full annihilator ideal for the Witt ring of an arbitrary field of characteristic unequal to two satisfying a non-vanishing condition on the powers of the fundamental ideal in the torsion part of the Witt ring. This settles a conjecture of Ongenae and Van Geel. This result could only be proved by first obtaining a new lower bound on the 2-adic valuation of Stirling numbers of the second kind.

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Stefan A. G. De Wannemacker. 2007-02-27. Annihilating polynomials for quadratic forms and Stirling numbers of the second kind. https://arxiv.org/abs/math/0702817

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