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Proceedings of the American Mathematical Society

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A van Kampen theorem for separable algebras

Author: Andy R. Magid
Journal: Proc. Amer. Math. Soc. 39 (1973), 483-488
MSC: Primary 13B05
MathSciNet review: 0313237
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Abstract: If the commutative ring $ S$ is the fibre product of $ {R_1}$ and $ {R_2}$ over $ R$, and if $ {R_2}$ maps onto $ R$, then the fundamental group of $ S$ is the profinite free product of the fundamental groups of $ {R_1}$ and $ {R_2}$ with the fundamental group of $ R$ amalgamated.

References [Enhancements On Off] (What's this?)

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Keywords: Separable algebra, profinite group, fibre product, cartesian square, co-cartesian square, fundamental group
Article copyright: © Copyright 1973 American Mathematical Society

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