Coxeter Matrix
See also
Coxeter GroupExplore with Wolfram|Alpha
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References
Buekenhout, F. and Parker, M. "The Number of Nets of the Regular Convex Polytopes in Dimension <=4." Disc. Math. 186, 69-94, 1998.Referenced on Wolfram|Alpha
Coxeter MatrixCite this as:
Weisstein, Eric W. "Coxeter Matrix." From MathWorld--A Wolfram Resource. https://mathworld.wolfram.com/CoxeterMatrix.html