《山东大学学报(理学版)》 ›› 2022, Vol. 57 ›› Issue (10): 59-65.doi: 10.6040/j.issn.1671-9352.0.2022.004
• • 上一篇
苟小丽,王维忠*
GOU Xiao-li, WANG Wei-zhong*
摘要: 设R是有单位元1≠0的有限交换环,R上的单位一-匹配双凯莱图记为GR=BC(R; R×, R×, {0}),其中R×表示R单位的集合。若一个k-正则图G的任意具有|λ|≠k的特征值λ满足|λ|≤2(k-1)1/2,则称这个k-正则图是Ramanujan图。给出R上的单位一-匹配双凯莱图GR及其线图是Ramanujan图的充要条件。
中图分类号:
[1] CAYLEY A. On the theory of group[J]. Proceedings of the London Mathematical Society, 1878, 9:126-233. [2] DE RESMINI M J, JUNGNICKEL D. Strongly regular semi-Cayley graphs[J]. Journal of Algebraic Combinatorics, 1992, 1(2):171-195. [3] KOVÁCS I, MALNIC A, MARUŠIC D, et al. One-matching bi-Cayley graphs over Abelian groups[J]. European Journal of Combinatorics, 2009, 30(2):602-616. [4] ZHOU J X, FENG Y Q. Cubic bi-Cayley graphs over Abelian groups[J]. European Journal of Combinatorics, 2014, 36:679-693. [5] ZHOU J X, FENG Y Q. The automorphisms of bi-Cayley graphs[J]. Journal of Combinatorial Theory, Series B, 2016, 116:504-532. [6] LIU X G. Energies of unitary one-matching bi-Cayley graphs over finite commutative rings[J]. Discrete Applied Mathematics, 2019, 259:170-179. [7] LUBOTZKY A, PHILLIPS R, SARNAK P. Ramanujan graphs[J]. Combinatorica, 1988, 8(3):261-277. [8] DAVIDOFF G, SARNAK P, VALETTE A. Elementary number theory, group theory and Ramanujan graphs[M]. Cambridge: Cambridge University Press, 2003. [9] LIU X G, LI B L. Distance powers of unitary Cayley graphs[J]. Applied Mathematics and Computation, 2016, 289:272-280. [10] LIU X G, ZHOU S M. Spectral properties of unitary Cayley graphs of finite commutative rings[J]. The Electronic Journal of Combinatorics, 2012, 19(4):1-19. [11] LIU X G, ZHOU S M. Quadratic unitary Cayley graphs of finite commutative rings [J]. Linear Algebra and its Applications, 2015, 479:73-90. [12] HOORY S, LINIAL N, WIGDERSON A. Expander graphs and their applications[J]. Bulletin of the American Mathematical Society, 2006, 43(4):439-561. [13] MURTY M R. Ramanujan graphs[J]. Journal of the Ramanujan Mathematics Society, 2003, 18(1):1-20. [14] LIU X G, ZHOU S M. Eigenvalues of Cayley graphs[J]. The Electronic Journal of Combinatorics, 2022, 29(2):1-164. [15] LIU X G, YAN C X. Unitary homogeneous bi-Cayley graphs over finite commutative rings [J]. Journal of Algebra and Its Applications, 2020, 19(9):2050173. [16] ATIYAH M F, MACDONALD I G. Introduction to commutative algebra[M]. London: Addison-Wesley, 1969. [17] DUMMIT D S, FOOTE R M. Abstract algebra[M]. 3th ed. New York: Wiley, 2003. [18] AKHTAR R, BOGGESS M, JACKSON-HENDERSON T, et al. On the unitary Cayley graph of a finite ring[J]. The Electronic Journal of Combinatorics, 2009, 16(1):1-13. [19] GANESAN N. Properties of rings with a finite number of zero-divisors[J]. Mathematische Annalen, 1964, 157(3):215-218. |
[1] | 卢鹏丽,刘文智. 图的广义距离谱[J]. 《山东大学学报(理学版)》, 2020, 55(9): 19-28. |
[2] | 王万禹,孟吉翔*,赵雪冰. 线图的限制性邻域连通度[J]. J4, 2012, 47(2): 56-59. |
|