411 REFERENCE · Wiktionary
Euler characteristic
Reference material by Wiktionary contributors. This retains its source identity and is not 411 news reporting.
English
Noun
en topology of a topological space The sum of even-dimensional Betti numbers minus the sum of odd-dimensional ones.
en A polygon's or polyhedron's Euler characteristic is just the number of corners minus the number of edges plus the number of faces.
en eponyms