Does there exist a finite kaleidoscope on the Euclidean plane?

Igor Vladimirovich Protasov @Igor-Protasov

13 September 2015 1 3K Report

A subset F of cardinality n>1is called a kaleidoscope if there is n-coloring of the plane such that any isometric copy of F has no monochrome points.If such a subset F exists then n>4.

Igor Protasov

Igor Vladimirovich Protasov

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