MAGAZINE
MATHEMATICS
374
4. J. A. Gallian, ContemporaryAbstract Algebra, 2nd edition, D. C. Heath and Company, Lexington, MA,
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5. W. H. Gustafson, What is the probability that two group elements commute?, Amer. Math. Monthly 80
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6. The Thirtieth William Lowell Putnam Mathematical Competition, MAA, December 6, 1969, Problem
B-2.
7. G. A. Miller, Groups containing the largest possible number of operators of order two, Amer. Math.
Monthly 12 (1905), 149-151.
8. J. Leavitt, G. J. Sherman, and M. J. Walker, Rewriteability in finite groups, Amer. Math. Monthly 99
(1992), 446-452.
9. M. D. Perez-Ramos, Groups with two normalizers, Arch. Math. 50 (1988), 199-203.
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11. G. J. Sherman, What is the probability an automorphism fixes a group element?, Amer. Math. Monthly
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and Its ReciprocalIs at LeastTwo (four proofs)
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-ROGER
B.
NELSEN
LEWIS AND CL.ARK COLLEGE
PORTLAND,
OR
97219
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