English

Regarding two conjectures on clique and biclique partitions

Combinatorics 2020-05-07 v1

Abstract

For a graph GG, let cp(G)cp(G) denote the minimum number of cliques of GG needed to cover the edges of GG exactly once. Similarly, let bpk(G)bp_k(G) denote the minimum number of bicliques (i.e. complete bipartite subgraphs of GG) needed to cover each edge of GG exactly kk times. We consider two conjectures -- one regarding the maximum possible value of cp(G)+cp(G)cp(G) + cp(\overline{G}) (due to de Caen, Erd\H{o}s, Pullman and Wormald) and the other regarding bpk(Kn)bp_k(K_n) (due to de Caen, Gregory and Pritikin). We disprove the first, obtaining improved lower and upper bounds on maxGcp(G)+cp(G)\max_G cp(G) + cp(\overline{G}), and we prove an asymptotic version of the second, showing that bpk(Kn)=(1+o(1))nbp_k(K_n) = (1+o(1))n.

Keywords

Cite

@article{arxiv.2005.02529,
  title  = {Regarding two conjectures on clique and biclique partitions},
  author = {Dhruv Rohatgi and John C. Urschel and Jake Wellens},
  journal= {arXiv preprint arXiv:2005.02529},
  year   = {2020}
}
R2 v1 2026-06-23T15:20:20.703Z