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A free subalgebra of the algebra of matroids

Henry Crapo·William Schmitt
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Abstract

This paper is an initial inquiry into the structure of the Hopf algebra of matroids with restriction-contraction coproduct. Using a family of matroids introduced by Crapo in 1965, we show that the subalgebra generated by a single point and a single loop in the dual of this Hopf algebra is free.

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Henry Crapo, William Schmitt. 2004-09-06. A free subalgebra of the algebra of matroids. https://arxiv.org/abs/math/0409028

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