G perfect (χ = ω on every induced subgraph) iff G has no odd hole / antihole (Chudnovsky et al 2006). Lovász 1972 (weak PGT).
G perfect (χ = ω on every induced subgraph) iff G has no odd hole / antihole (Chudnovsky et al 2006). Lovász 1972 (weak PGT).