MathDB
Form groups

Source: APMO 1996

March 12, 2006
combinatorics unsolvedcombinatorics

Problem Statement

The National Marriage Council wishes to invite nn couples to form 17 discussion groups under the following conditions: (1) All members of a group must be of the same sex; i.e. they are either all male or all female. (2) The difference in the size of any two groups is 0 or 1. (3) All groups have at least 1 member. (4) Each person must belong to one and only one group. Find all values of nn, n1996n \leq 1996, for which this is possible. Justify your answer.