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A Collective Property of Trees and Chemical Trees
Journal of Chemical Information and Computer Sciences, 1998The Wiener index (W) and the Hosoya polynomial (H) have been calculated for all trees (and thus for all chemical trees) with 20 and fewer vertices. Corroborating an earlier observation (Razinger, M. et al. J. Chem. Inf. Comput. Sci. 1985, 25, 23−27), we show that the ability of W to distinguish between nonisomorphic n-vertex trees (respectively ...
Ivan Gutman
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A Linear Algorithm for the Hyper-Wiener Index of Chemical Trees
Journal of Chemical Information and Computer Sciences, 2001 An algorithm with a complexity linear in the number of vertices is proposed for the computation of the Hyper-Wiener index of chemical trees. This complexity is the best possible. Computational experience for alkanes is reported.
Roberto Aringhieri +2 more
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Counting Chemical Structures Resembling Trees
2018 International Conference on Advances in Computing, Communications and Informatics (ICACCI), 2018Trees have been used for counting chemical structures of non-isomorphic forms. Graph enumeration can be either isomorphic or non-isomorphic. Isomorphic tree enumeration arises in the context of listing all isomorphic subtrees of a given graph whereas non-isomorphic enumeration lists all unique trees that satisfy given constraints. We study the chemical
Bhadrachalam Chitturi
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The σ-Irregularity of Chemical Trees
Match - Communications in Mathematical and in Computer Chemistry, 2023 The $sigma$-irregularity index is a variant of the well-established Albertson irregularity index. For a graph $G = (V, E)$ it is defined as $sigma (G) = Sigma _{uvin E}(d(u) − d(v))^2$, where $d(u)$ and $d(v)$ denote the degrees of vertices $u$ and $v ...
Žana Kovijanić Vukićević +4 more
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The maximum Randić index of chemical trees with k pendants
Discrete Mathematics, 2009 A tree is a chemical tree if its maximum degree is at most 4. Hansen and Mélot [P. Hansen, H. Mélot, Variable neighborhood search for extremal graphs 6: analyzing bounds for the connectivity index, J. Chem. Inf. Comput. Sci.
Wai Chee Shiu
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The Average Wiener Index of Trees and Chemical Trees
Journal of Chemical Information and Computer Sciences, 1999Meir and Moon (J. Combin. Theory 1970, 8, 99−103) reported a combinatorial formula for the average value of the distance between a pair of vertices in the class of all labeled trees with a fixed number (= n) of vertices. From this result an expression for the average Wiener index 〈Wn〉lab of labeled n-vertex trees follows immediately.
Andrey A. Dobrynin, Ivan Gutman
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Chemical trees enumeration algorithms
Quarterly Journal of the Belgian, French and Italian Operations Research Societies, 2003zbMATH Open Web Interface contents unavailable due to conflicting licenses.
Roberto Aringhieri +2 more
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Risk-based monitoring of chemical substances in food: Prioritization by decision trees
Food Control, 2018 Monitoring programs for food safety hazards are increasingly set up on a risk basis. In order to include the most relevant chemical substances for food products within such a program, a prioritization is needed.
Dorgelo, F.O. +7 more
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Mining environmental chemicals with boosted trees
Proceedings of the 35th Annual ACM Symposium on Applied Computing, 2020In response to scientific reports and legislative actions, the United States Environmental Protection Agency (EPA) launched an Endocrine Disruptor Screening Program (EDSP). The overarching aim of this program is to develop novel analytical and computational tools and methods for the detection of environmental chemicals causing aberrations in estrogen ...
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