{"title":"Faudree-Lehel猜想的推广对随机图几乎成立","authors":"J. Przybylo","doi":"10.1002/rsa.21058","DOIUrl":null,"url":null,"abstract":"The irregularity strength of a simple graph G=(V,E) , denoted s(G) is a certain measure of the level of irregularity of a graph. It indicates how hard it is to make an irregular multigraph of G via multiplication of its selected edges. It is however more commonly set forth through k‐weightings, that is, mappings ω:E→{1,2,…,k} , assigning every vertex v∈V the weighted degree σ(v):=∑e∋vω(e) . In this setting, s(G) is precisely defined as the least k admitting a k‐weighting of G which attributes pairwise distinct weighted degrees to all vertices of G. It is known that s(G)>n/d in the case of d‐regular graphs with order n and d>1 . An open conjecture of Faudree and Lehel from the 1980s states that s(G)≤n/d+c in turn for some finite constant c independent of d. It is believed that the natural strengthening of this conjecture toward all graphs where d is substituted by the minimum degree δ should also hold. We confirm this supposition in the case of random graphs. Namely, we show that asymptotically almost surely the generalization of Faudree‐Lehel Conjecture holds for a random graph G∈𝒢(n,p) for any constant p, that is, that s(G) takes one of the three values: ⌈n/δ⌉ , ⌈n/δ⌉+1 , or ⌈n/δ⌉+2 . This is implied by the fact that a.a.s. p−1","PeriodicalId":0,"journal":{"name":"","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2021-11-07","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":"1","resultStr":"{\"title\":\"A generalization of Faudree–Lehel conjecture holds almost surely for random graphs\",\"authors\":\"J. Przybylo\",\"doi\":\"10.1002/rsa.21058\",\"DOIUrl\":null,\"url\":null,\"abstract\":\"The irregularity strength of a simple graph G=(V,E) , denoted s(G) is a certain measure of the level of irregularity of a graph. It indicates how hard it is to make an irregular multigraph of G via multiplication of its selected edges. It is however more commonly set forth through k‐weightings, that is, mappings ω:E→{1,2,…,k} , assigning every vertex v∈V the weighted degree σ(v):=∑e∋vω(e) . In this setting, s(G) is precisely defined as the least k admitting a k‐weighting of G which attributes pairwise distinct weighted degrees to all vertices of G. It is known that s(G)>n/d in the case of d‐regular graphs with order n and d>1 . An open conjecture of Faudree and Lehel from the 1980s states that s(G)≤n/d+c in turn for some finite constant c independent of d. It is believed that the natural strengthening of this conjecture toward all graphs where d is substituted by the minimum degree δ should also hold. We confirm this supposition in the case of random graphs. Namely, we show that asymptotically almost surely the generalization of Faudree‐Lehel Conjecture holds for a random graph G∈𝒢(n,p) for any constant p, that is, that s(G) takes one of the three values: ⌈n/δ⌉ , ⌈n/δ⌉+1 , or ⌈n/δ⌉+2 . This is implied by the fact that a.a.s. p−1\",\"PeriodicalId\":0,\"journal\":{\"name\":\"\",\"volume\":null,\"pages\":null},\"PeriodicalIF\":0.0,\"publicationDate\":\"2021-11-07\",\"publicationTypes\":\"Journal Article\",\"fieldsOfStudy\":null,\"isOpenAccess\":false,\"openAccessPdf\":\"\",\"citationCount\":\"1\",\"resultStr\":null,\"platform\":\"Semanticscholar\",\"paperid\":null,\"PeriodicalName\":\"\",\"FirstCategoryId\":\"100\",\"ListUrlMain\":\"https://doi.org/10.1002/rsa.21058\",\"RegionNum\":0,\"RegionCategory\":null,\"ArticlePicture\":[],\"TitleCN\":null,\"AbstractTextCN\":null,\"PMCID\":null,\"EPubDate\":\"\",\"PubModel\":\"\",\"JCR\":\"\",\"JCRName\":\"\",\"Score\":null,\"Total\":0}","platform":"Semanticscholar","paperid":null,"PeriodicalName":"","FirstCategoryId":"100","ListUrlMain":"https://doi.org/10.1002/rsa.21058","RegionNum":0,"RegionCategory":null,"ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":null,"EPubDate":"","PubModel":"","JCR":"","JCRName":"","Score":null,"Total":0}
A generalization of Faudree–Lehel conjecture holds almost surely for random graphs
The irregularity strength of a simple graph G=(V,E) , denoted s(G) is a certain measure of the level of irregularity of a graph. It indicates how hard it is to make an irregular multigraph of G via multiplication of its selected edges. It is however more commonly set forth through k‐weightings, that is, mappings ω:E→{1,2,…,k} , assigning every vertex v∈V the weighted degree σ(v):=∑e∋vω(e) . In this setting, s(G) is precisely defined as the least k admitting a k‐weighting of G which attributes pairwise distinct weighted degrees to all vertices of G. It is known that s(G)>n/d in the case of d‐regular graphs with order n and d>1 . An open conjecture of Faudree and Lehel from the 1980s states that s(G)≤n/d+c in turn for some finite constant c independent of d. It is believed that the natural strengthening of this conjecture toward all graphs where d is substituted by the minimum degree δ should also hold. We confirm this supposition in the case of random graphs. Namely, we show that asymptotically almost surely the generalization of Faudree‐Lehel Conjecture holds for a random graph G∈𝒢(n,p) for any constant p, that is, that s(G) takes one of the three values: ⌈n/δ⌉ , ⌈n/δ⌉+1 , or ⌈n/δ⌉+2 . This is implied by the fact that a.a.s. p−1