1. The core of a vertex-transitive complementary prismMarko Orel, 2023, original scientific article Abstract: The complementary prism ▫$\Gamma \overline{\Gamma}$▫ is obtained from the union of a graph ▫$\Gamma$▫ and its complement ▫$\overline{\Gamma}$▫ where each pair of identical vertices in ▫$\Gamma$▫ and ▫$\overline{\Gamma}$▫ is joined by an edge. It generalizes the Petersen graph, which is the complementary prism of the pentagon. The core of a vertex-transitive complementary prism is studied. In particular, it is shown that a vertex-transitive complementary prism ▫$\Gamma \overline{\Gamma}$▫ is a core, i.e. all its endomorphisms are automorphisms, whenever ▫$\Gamma$▫ is a core or its core is a complete graph. Keywords: graph homomorphism, complementary prism, self-complementary graph, vertex-transitive graph, core Published in RUP: 06.11.2023; Views: 764; Downloads: 5 Full text (305,54 KB) |
2. Ramamurthy, Balaji; Bapat, Ravindra Bhalchandra; Goel, Shivani: Distance matrices perturbed by Laplacians. (English summary). - Appl. Math. 65 (2020), no. 5, 599-607.Marko Orel, 2021, review, book review, critique Keywords: Laplacian of a graph, positive definite matrices, weighted graphs Published in RUP: 18.10.2021; Views: 792; Downloads: 7 Link to full text |
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6. Beasley, LeRoy B., Kang, Kyung-Tae, Song, Seok-Zun: Isolation numbers of integer matrices and their preservers. (English summary). - Bull. Korean Math. Soc. 57 (2020), no. 3, 535-545Marko Orel, 2021, review, book review, critique Keywords: preserver problems, matrices with nonnegative coefficients, isolation number Published in RUP: 06.05.2021; Views: 797; Downloads: 7 Link to full text |
7. Ahmia, Moussa(DZ-UJ-M); Belbachir, Hacène(DZ-BOUMM-RCL) p,q-analogue of a linear transformation preserving log-convexity. (English summary) Indian J. Pure Appl. Math. 49 (2018), no. 3, 549-557Marko Orel, 2019, review, book review, critique Keywords: log-convex sequence, p-q-binomial coefficient, q-binomial coefficient Published in RUP: 28.06.2019; Views: 1966; Downloads: 16 Link to full text |
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