Via non-sex blog MarginalRevolution
What is the minimum number of condoms required for safe sex in each case:
(a) two men with two women
(b) one man with three women or three men with one woman
(c) three men with each other
(d) 2k+1 men with one woman
(e) m men and n women
Original Source: “Ilan Vardi, Computational Recreations in Mathematica, Addison Wesley,
1991, p. 205



