Patch Colorings and Rigid Colorings of the Rational n-Space
نویسندگان
چکیده
We investigate k-colorings of the rational n-space, Q, such that any two points at distance one get distinct colors. Two types of colorings are considered: patch colorings where the colors occupy open sets with parts of their boundary, and rigid colorings which uniquely extend from any open subset of Q. We prove that the existence of a patch k-coloring of Q implies the existence of a k-coloring of R. We show that every 2-coloring of Q or Q, and every 4-coloring of Q is rigid. We also construct a rigid 3-coloring of Q. © 2001 Elsevier Science
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ورودعنوان ژورنال:
- J. Comb. Theory, Ser. B
دوره 84 شماره
صفحات -
تاریخ انتشار 2002