A random analogue of Gilbreath's conjecture

Abstract

A well-known conjecture of Gilbreath, and independently Proth from the 1800s, states that if $a_{0,n}=p_n$ denotes the $n^{\text{th}}$ prime number and $a_{i,n}=|a_{i-1,n}-a_{i-1,n+1}|$ for $i,n\ge 1$, then $a_{i,1}=1$ for all $i\ge 1$. It has been postulated repeatedly that the property of having $a_{i,1}=1$ for $i$ large enough should hold for any choice of initial $(a_{0,n}{)}_{n\ge 1}$ provided that the gaps $a_{0,n+1}-a_{0,n}$ are not too large and are sufficiently random. We prove (a precise form of) this postulate.

arXiv comment14 pages, 1 figure