Category
page 1Lemmas in group theory
Burnside's lemma
lemma stating that, given a finite group G acting on a set, the number of orbits times |G| equals the sum (over every element of G) of the numbers of fixed points
ping-pong lemma
theorem about sufficient conditions for ensuring that that several elements in a group acting on a set freely generate a free subgroup of that group
Zassenhaus lemma
technical lemma in group theory
Frattini's argument
lemma in group theory