{"paper":{"title":"Maxima of the Q-index: degenerate graphs","license":"http://arxiv.org/licenses/nonexclusive-distrib/1.0/","headline":"","cross_cats":[],"primary_cat":"math.CO","authors_text":"V. Nikiforov","submitted_at":"2013-09-19T02:28:42Z","abstract_excerpt":"Let $G$ be a $k$-degenerate graph of order $n.$ It is well-known that $G\\ $has no more edges than $S_{n,k},$ the join of a complete graph of order $k$ and an independent set of order $n-k.$ In this note it is shown that $S_{n,k}$ is extremal for some spectral parameters of $G$ as well. More precisely, letting $\\mu\\left( H\\right) $ and $q\\left( H\\right) $ denote the largest eigenvalues of the adjacency matrix and the signless Laplacian of a graph $H,$ the inequalities \\[ \\mu\\left( G\\right) <\\mu\\left( S_{n,k}\\right) \\text{ and }q\\left( G\\right) <q\\left( S_{n,k}\\right) \\] hold, unless $G=S_{n,k}$"},"claims":{"count":0,"items":[],"snapshot_sha256":"258153158e38e3291e3d48162225fcdb2d5a3ed65a07baac614ab91432fd4f57"},"source":{"id":"1309.4837","kind":"arxiv","version":2},"verdict":{"id":null,"model_set":{},"created_at":null,"strongest_claim":"","one_line_summary":"","pipeline_version":null,"weakest_assumption":"","pith_extraction_headline":""},"references":{"count":0,"sample":[],"resolved_work":0,"snapshot_sha256":"258153158e38e3291e3d48162225fcdb2d5a3ed65a07baac614ab91432fd4f57","internal_anchors":0},"formal_canon":{"evidence_count":0,"snapshot_sha256":"258153158e38e3291e3d48162225fcdb2d5a3ed65a07baac614ab91432fd4f57"},"author_claims":{"count":0,"strong_count":0,"snapshot_sha256":"258153158e38e3291e3d48162225fcdb2d5a3ed65a07baac614ab91432fd4f57"},"builder_version":"pith-number-builder-2026-05-17-v1"}