On Eisenstein's problem
We show that, with suitable modification, the upper bound estimates of Stolt for the fundamental integer solutions of the Diophantine equation Au²+Buv+Cv²=N, where A>0, N≠0 and B²-4AC is positive and nonsquare, in fact characterize the fundamental solutions. As a corollary, we get a corresponding result for the equation u²-dv²=N, where d is positive and nonsquare, in which case the upper bound estimates were obtained by Nagell and Chebyshev.
The goal of this paper is to outline the proof of a conjecture of Gelfond [6] (1968) in a recent work in collaboration with Christian Mauduit [11] concerning the sum of digits of prime numbers, reflecting the lecture given in Edinburgh at the Journées Arithmétiques 2007.
Grosswald’s conjecture is that g(p), the least primitive root modulo p, satisfies g(p) ≤ √p - 2 for all p > 409. We make progress towards this conjecture by proving that g(p) ≤ √p -2 for all and for all .
A set of distinct positive integers is said to be gcd-closed if for all . Shaofang Hong conjectured in 2002 that for a given positive integer there is a positive integer depending only on , such that if , then the power LCM matrix defined on any gcd-closed set is nonsingular, but for , there exists a gcd-closed set such that the power LCM matrix on is singular. In 1996, Hong proved and noted for all . This paper develops Hong’s method and provides a new idea to calculate...