MathDB

3

Part of 2006 Singapore MO Open

Problems(1)

Sequence of Prime

Source: Singapore Mathematical Olympiad 2006 Problem 3

7/7/2006
Consider the sequence p1,p2,...p_{1},p_{2},... of primes such that for each i≥2i\geq2, either pi=2pi−1−1p_{i}=2p_{i-1}-1 or pi=2pi−1+1p_{i}=2p_{i-1}+1. Show that any such sequence has a finite number of terms.
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