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Some cyclic inequalities

Published online by Cambridge University Press:  20 January 2009

V. J. Baston
Affiliation:
The University, Southampton S09 5NH
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In this note we prove some cyclic inequalities which are generalisations of known results. We shall assume throughout that ai+n = ai ≧ 0 for all i, that no denominator in the statement of a result vanishes and finally that p, m and q are positive integers. We shall also use A(i, m) to denote with the convention that A(i, 0) = 0. The most interesting of our results is probably Theorem 2 since, in the special case p = 1, m = 2, r = 0, it gives a lower bound of ⅓n for the Shapiro sum . Although it is by no means best possible, see (2), our method implicitly gives a really simple way of obtaining this lower bound which, incidentally, is an improvement on Rankin's original result (5).

Type
Research Article
Copyright
Copyright © Edinburgh Mathematical Society 1974

References

REFERENCES

(1) Boarder, J. C. and Daykin, D. E., Inequalities for certain cyclic sums II, Proc. Edinburgh Math. Soc. 18 (1973), 209218.CrossRefGoogle Scholar
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(6) Zulauf, A., Note on some inequalities, Math. Gaz. 43 (1959), 4244.Google Scholar