Feit-Thompson Theorem
Every finite simple group (that is not cyclic) has even group order, and the group order of every finite simple noncommutative group is doubly even, i.e., divisible by 4 (Feit and Thompson 1963).
The proof of the Feit-Thompson theorem took up an entire journal issue (Feit and Thompson 1963).
See also
Burnside's Conjecture, Burnside Problem, Feit-Thompson Conjecture, Finite Group, Group Order, Simple Group, Solvable GroupExplore with Wolfram|Alpha
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References
Guy, R. K. Unsolved Problems in Number Theory, 2nd ed. New York: Springer-Verlag, p. 81, 1994.Feit, W. and Thompson, J. G. "A Solvability Criterion for Finite Groups and Some Consequences." Proc. Nat. Acad. Sci. USA 48, 968-970, 1962.Feit, W. and Thompson, J. G. "Solvability of Groups of Odd Order." Pacific J. Math. 13, 775-1029, 1963.Referenced on Wolfram|Alpha
Feit-Thompson TheoremCite this as:
Weisstein, Eric W. "Feit-Thompson Theorem." From MathWorld--A Wolfram Resource. https://mathworld.wolfram.com/Feit-ThompsonTheorem.html
