MathDB

4

Part of 1993 Spain Mathematical Olympiad

Problems(1)

infinitely many multiples of prime p of the form 1111...1, besides 2 and 5

Source: Spanish Mathematical Olympiad 1993 P4

8/1/2018
Prove that for each prime number distinct from 22 and 55 there exist infinitely many multiples of pp of the form 1111...11111...1.
number theoryprimemultiple