Faudree–Favaron–Li conjecture on $P_5$-free irredundance perfect graphs

A graph is $P_5$-free if it has no induced subgraph isomorphic to the path $P_5$. Faudree–Favaron–Li conjecture. Any $P_5$-free graph is irredundance perfect. Puech proved this consequence by showing that every graph containing neither $P_6$ nor a specified induced graph $H$ is irredundance perfect; the conjecture is therefore solved.