CLASSIFICATION OF THE SUBSET OF PRIME NUMBERS INDUCED BY COLOURING A CLASS OF GRAPHS

Let P denote the set of all prime numbers, and D(?) P. Let G(Z, D) denote the graph with the integers as its vertex set and the edges between those pairs of integers with absolute difference in the set D. Eggleton, Erd(?)s and Skilton proved in J. Combinatorial Theory (B), 39(1985), 86—100 that for any D(?)P, the