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On the greatest prime Factor of a polynomial

Published online by Cambridge University Press:  20 January 2009

M. Keates
Affiliation:
Department of Pure Mathematics, University College, Cardiff
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Let ƒ(x) be a non-linear polynomial with rational integer coefficients, and for integral x let P(x) denote the greatest (positive) prime factor of ƒ(x). Pólya (1) has proved that if ƒ(x) is of degree 2 and has distinct roots then P(x)→∞ as x→∞. It is probably well-known that, provided ƒ(x) has distinct roots, this is true whatever the degree of ƒ(x). There does not appear to be a proof of this in the literature, but it is easily deducible from a result of Siegel (2). These results, however, are non-effective, although effective results have been obtained for a number of special polynomials. Chowla (3) has proved that, if ƒ(x) = x2 +1, then P(x)>C log log x, where C is an absolute positive constant. Analogous results have been proved for some polynomials of the form ax2+b and for some of the form ax3 + b by Mahler and Nagell respectively (4).

Type
Research Article
Copyright
Copyright © Edinburgh Mathematical Society 1969

References

REFERENCES

(1) Pólya, G.Zur arithmetischen Untersuchung der Polynome, Math. Zeitschrift, 1 (1918), 143148.CrossRefGoogle Scholar
(2) Siegel, C. L. (extract from a letter to L. J. Mordell), The integer solutions of the equation y2 = ax 3 + bx 2 + cx + d, J. London Math. Soc, 1 (1926), 6668.Google Scholar
(3) Chowla, S.The greatest prime factor of x 2 + 1, J. London Math. Soc, 10 (1935), 117120.CrossRefGoogle Scholar
(4) Mahler, K.Uber den grössten Primteiler spezieller Polynome zweiten Grades, Archivfor Mathem. og Natur., 41 (1934), No. 6.Google Scholar
(5) Baker, A.The Diophantine equation y2 = ax 3 + bx 2 + cx + d, J. London Math. Soc, 43 (1968), 19.CrossRefGoogle Scholar
(6) Baker, A.Contributions to the theory of Diophantine equations, Trans. Roy. Soc. London Ser. A, 263 (1968), 173208.Google Scholar