MathDB
2018 PUMaC Individual Finals A3

Source:

January 8, 2019
PuMACIndividual Finalsnumber theoryprime numbers

Problem Statement

We say that the prime numbers p1,,pnp_1,\dots,p_n construct the graph GG if we can assign to each vertex of GG a natural number whose prime divisors are among p1,,pnp_1,\dots,p_n and there is an edge between two vertices in GG if and only if the numbers assigned to the two vertices have a common divisor greater than 11. What is the minimal nn such that there exist prime numbers p1,,pnp_1,\dots,p_n which construct any graph GG with NN vertices?