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Problem GT-002 — the Ramsey number R(5,5)

goaldef

Is R(5,5) = 43? Erdős' remark that an alien civilisation demanding R(6,6) should be fought rather than answered gives the flavour: the values are bounded but essentially uncomputable, and this is the smallest unknown diagonal case.

def goal : Prop :=
  Conjectura.GraphTheory.ArrowsTo 43 5 5 ∧ ¬ Conjectura.GraphTheory.ArrowsTo 42 5 5

Builds on

import Conjectura.Problems.GT002.Statement · maintainer — open · raw source

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