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TERNARY UNIVERSAL SUMS OF GENERALIZED PENTAGONAL NUMBERS
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 Title & Authors
TERNARY UNIVERSAL SUMS OF GENERALIZED PENTAGONAL NUMBERS
Oh, Byeong-Kweon;
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 Abstract
For an integer , every integer of the form = with x is said to be a generalized m-gonal number. Let and k be positive integers. The quadruple (k, a, b, c) is said to be universal if for every nonnegative integer n there exist integers x, y, z such that n = . Sun proved in [16] that, when k = 5 or , there are only 20 candidates for universal quadruples, which h listed explicitly and which all involve only the case of pentagonal numbers (k = 5). He veri ed that six of the candidates are in fact universal and conjectured that the remaining ones are as well. In a subsequent paper [3], Ge and Sun established universality for all but seven of the remaining candidates, leaving only (5, 1, 1, t) for t = 6, 8, 9, 10, (5, 1, 2, 8) and (5, 1, 3, s) for s = 7, 8 as candidates. In this article, we prove that the remaining seven quadruples given above are, in fact, universal.
 Keywords
generalized polygonal numbers;ternary universal sums;
 Language
English
 Cited by
 References
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