Nagao’s theorem

For any integral domain k, the group of n×n invertible matrices with coefficients in k[t] is the amalgamated free product of invertible matrices over k and invertiblePlanetmathPlanetmath upper triangular matricesMathworldPlanetmath over k[t], amalgamated over the upper triangular matrices of k. More compactly

Title Nagao’s theorem
Canonical name NagaosTheorem
Date of creation 2013-03-22 13:58:31
Last modified on 2013-03-22 13:58:31
Owner bwebste (988)
Last modified by bwebste (988)
Numerical id 6
Author bwebste (988)
Entry type Theorem
Classification msc 20G15