## Homogeneous Drift

(This post is part of Polymath5; see Gowers’ weblog to understand what I’m talking about.)

The following trees represent ways to assign primes in a completely multiplicative sequence. If a leaf is labeled {N,k}, it means that the corresponding assignment has $\sum_{i=N-k+1}^N x_i$ with absolute value “drift”.

drift = 2

drift = 3

drift = 4

drift = 5