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Higher Monotonicity Properties of Certain Sturm-Liouville Functions. III

Published online by Cambridge University Press:  20 November 2018

Lee Lorch
Affiliation:
York University, Toronto, Ontario
M. E. Muldoon
Affiliation:
(L. L. and M. E. M.) Ampex Corporation, Redwood City, California (P. S.)
Peter Szego
Affiliation:
(L. L. and M. E. M.) Ampex Corporation, Redwood City, California (P. S.)
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A Sturm-Liouville function is simply a non-trivial solution of the Sturm-Liouville differential equation

(1.1)

considered, together with everything else in this study, in the real domain. The associated quantities whose higher monotonicity properties are determined here are defined, for fixed λ > –1, to be

(1.2)

where y(x) is an arbitrary (non-trivial) solution of (1.1) and x1, x2, … is any finite or infinite sequence of consecutive zeros of any non-trivial solution z(x) of (1.1) which may or may not be linearly independent of y(x). The condition λ > –1 is required to assure convergence of the integral defining Mk, and the function W(x) is taken subject to the same restriction.

Type
Research Article
Copyright
Copyright © Canadian Mathematical Society 1970

References

1. Bochner, S., Completely monotone functions of the Laplace operator for torus and sphere, Duke Math. J. 3 (1937), 488502.Google Scholar
2. Cooke, R. G., A monotonie property of Bessel functions, J. London Math. Soc. 12 (1937), 180185.Google Scholar
3. Dubourdieu, J., Sur un théorème de M. S. Bernstein relatif à la transformation de Laplace- Stieltjes, Compositio Math. 7 (1939), 96111.Google Scholar
4. Duff, G. F. D., Positive elementary solutions and completely monotonie functions, J. Math. Anal. Appl. 27 (1969), 469494.Google Scholar
5. Hartman, P., On differential equations and the function JM 2 + YJ-, Amer. J. Math. 83 (1961), 154188.Google Scholar
6. Hartman, P., Ordinary differential equations (Wiley, New York, 1964).Google Scholar
7. Hartman, P. and Wintner, A., On nonconservative linear oscillators of low frequency, Amer. J. Math. 70 (1948), 529539.Google Scholar
8. Knopp, K., Theory and application of infinite series, Second English ed. (Blackie and Son, London and Glasgow, 1951).Google Scholar
9. Ch.-J. de La Vallée, Poussin, Cours d'analyse infinitésimale, Vol. 1, Twelfth ed. (Librairie Universitaire, Louvain; Gauthier-Villars, Paris, 1959).Google Scholar
10. Lorch, L., Comparison of two formulations of Sonin's theorem and of their respective applications to Bessel functions, Studia Sci. Math. Hungar. 1 (1966), 141145.Google Scholar
11. Lorch, L. and Moser, L., A remark on completely monotonie sequences, with an application to summability, Can. Math. Bull. 6 (1963), 171173.Google Scholar
12. Lorch, L. and Szego, P., Higher monotonicity properties of certain Sturm-Liouville functions, Acta Math. 109 (1963), 5573.Google Scholar
13. Lorch, L. and Szego, P., Higher monotonicity properties of certain Sturm-Liouville functions. II, Bull. Acad. Polon. Sci. Sér. Sci. Math. Astronom. Phys. 11 (1963), 455457.Google Scholar
14. Lorch, L. and Szego, P., Monotonicity of the differences of zeros of Bessel functions as a function of order, Proc. Amer. Math. Soc. 15 (1964), 9196.Google Scholar
15. Lorch, L. and Szego, P., A Bessel function inequality connected with stability of least square smoothing. II, Glasgow Math. J. 9 (1968), 119122.Google Scholar
16. Lorch, L., Muldoon, M. E., and Szego, P., Higher monotonicity properties of certain Sturm- Liouville functions, IV (in preparation).Google Scholar
17. Makai, E., On a monotonie property of certain Sturm-Liouville functions, Acta Math. Acad» Sci. Hungar. 8 (1952), 165172.Google Scholar
18. Muldoon, M. E., Extension of a result of L. Lorch and P. Szego on higher monotonicity, Can. Math. Bull. 11 (1968), 447451.Google Scholar
19. Muldoon, M. E., Elementary remarks on multiply monotonie functions and sequences, Can. Math. Bull. 14 (1971), to appear.Google Scholar
20. Pölya, G. and Szegö, G., Aufgaben und Lehrsàtze aus der Analysis, Zweiter Band, 2te Aufl., Die Grundlehren der mathematischen Wissenschaften in Einzeldarstellungen mit besonderer Beriicksichtigung der Anwendungsgebiete, Bd. XX (Springer-Verlag, Berlin-Göttingen-Heidelberg, 1954).Google Scholar
21. Schoenberg, I. J., Metric spaces and completely monotone functions, Ann. of Math. (2) 89 (1938), 811841.Google Scholar
22. Sturm, Ch., Mémoire sur les équations différentielles du second ordre, J. Math. Pures Appl. 1 (1836), 106186.Google Scholar
23. Trench, W. F., On the stability of midpoint smoothing with Legendre polynomials, Proc. Amer. Math. Soc. 18 (1967), 191199.Google Scholar
24. Trench, W. F., Bounds on the generating functions of certain smoothing operations, Proc. Amer. Math. Soc. 18 (1967), 200206.Google Scholar
25. Vosmansky, J., The monotonicity of extremants of integrals of the differential equation y” + q(t)y = 0, Arch. Math. (Brno) 2 (1966), 105111.Google Scholar
26. Watson, G. N., A treatise on the theory of Bessel functions, Second ed. (Cambridge Univ. Press, Cambridge, England; Macmillan, New York, 1944).Google Scholar
27. Widder, D. V., The Laplace transform (Princeton Univ. Press, Princeton, N.J., 1941).Google Scholar
28. Wilf, H. S., The stability of smoothing by least squares, Proc. Amer. Math. Soc. 15 (1964), 933937; Errata: ibid. 17 (1966), 542.Google Scholar
29. Wiman, A., Uber eine Stabilitàtsfrage in der Théorie der linearen Differentialgleichungen, Acta Math. 66 (1936), 121145.Google Scholar