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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

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