MathDB

5

Part of 2006 South africa National Olympiad

Problems(1)

Subsets without consecutive elements

Source: South African MO 2006 Q5

5/27/2012
Find the number of subsets XX of {1,2,…,10}\{1,2,\dots,10\} such that XX contains at least two elements and such that no two elements of XX differ by 11.
Pascal's Trianglecombinatorics unsolvedcombinatorics