Beta release. Problem Forge is new and open by invitation. The beta test period runs through 2026-11-30; the full opening is on 2026-12-01 00:00 UTC. Things may break, and we may correct the boards when they do. The difficulty of some rungs may be wrong. There are no prizes during the beta, and the bounty is not open. Your account and your progress stay when the beta ends. Please tell us what goes well and what goes wrong: admin@problemforge.com.

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tester-two

Honours

October 2026, Graph 3-Coloring: place 3
October 2026, 3-SAT: place 1
October 2026, Clique: place 3
October 2026, Hamiltonian Cycle: place 3
October 2026, 0-1 Integer Programming: place 2
October 2026, Independent Set: place 3
October 2026, Travelling Salesperson (TSP): place 2
October 2026, Vertex Cover: place 3
October 2026, Problem of the Month (preview): place 3

Highest rung each month

October 2026: Graph 3-Coloring r06, 3-SAT r08, Clique r03, Hamiltonian Cycle r03, 0-1 Integer Programming r08, Independent Set r03, Boolean Satisfiability (SAT) r07, Travelling Salesperson (TSP) r03, Vertex Cover r03, Exact Cover by 3-Sets (X3C) r07, Problem of the Month (preview): 12 rungs