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Binomial andQ-Binomial Coefficient Inequalities Related to the Hamiltonicity of the Kneser Graphs and TheirQ-Analogues

✍ Scribed by W.Edwin Clark; Mourad E.H. Ismail


Publisher
Elsevier Science
Year
1996
Tongue
English
Weight
449 KB
Volume
76
Category
Article
ISSN
0097-3165

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✦ Synopsis


The Kneser graph K(n, k) has as vertices all the k-subsets of a fixed n-set and has as edges the pairs [A, B] of vertices such that A and B are disjoint. It is known that these graphs are Hamiltonian if ( n&1 k&1 ) ( n&k k ) for n 2k+1. We determine asymptotically for fixed k the minimum value n=e(k) for which this inequality holds. In addition we give an asymptotic formula for the solution of k1 (n) 1 (n&2k+1)= 1 2 (n&k+1) for n 2k+1, as k Ä , when n and k are not restricted to take integer values. We also show that for all prime powers q and n 2k, k 1, the q-analogues K q (n, k) are Hamiltonian by consideration of the analogous inequality for q-binomial coefficients.