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Source labels openWritten on the Wall II · Combinatorics

Written on the Wall II - Conjecture 61

WOWII Conjecture 61

For a simple connected graph GG, the size f(G)f(G) of a largest induced forest satisfies f(G)residue(G)+diam(G)/3f(G) \ge \mathrm{residue}(G) + \lceil \mathrm{diam}(G) / 3 \rceil, where residue(G)\mathrm{residue}(G) is the Havel-Hakimi residue and diam(G)\mathrm{diam}(G) is the diameter of GG.

See: Favaron, Mahéo, Saclé (1991) for the residue; DeLaVina's Graffiti.pc for the conjecture.

Source checked Jul 26, 20261 pinned Lean statementInspect problem
Source labels openWritten on the Wall II · Combinatorics

Written on the Wall II - Conjecture 65

WOWII Conjecture 65:

For a simple connected graph GG, the size f(G)f(G) of a largest induced forest satisfies f(G)dist_min(A)+dist_min(M)/3f(G) \ge \operatorname{dist\_min}(A) + \lceil \operatorname{dist\_min}(M) / 3 \rceil, where AA is the set of minimum-degree vertices, MM is the set of maximum-degree vertices, and dist_min(S)=minvSdist(v,S)\operatorname{dist\_min}(S) = \min_{v \notin S} \operatorname{dist}(v, S) (see distMin).

Source checked Jul 26, 20261 pinned Lean statementInspect problem