Title
Restricted linear congruences
Abstract
In this paper, using properties of Ramanujan sums and of the discrete Fourier transform of arithmetic functions, we give an explicit formula for the number of solutions of the linear congruence a1x1+⋯+akxk≡b(modn), with gcd⁡(xi,n)=ti (1≤i≤k), where a1,t1,…,ak,tk,b,n (n≥1) are arbitrary integers. As a consequence, we derive necessary and sufficient conditions under which the above restricted linear congruence has no solutions. The number of solutions of this kind of congruence was first considered by Rademacher in 1925 and Brauer in 1926, in the special case of ai=ti=1 (1≤i≤k). Since then, this problem has been studied, in several other special cases, in many papers; in particular, Jacobson and Williams [Duke Math. J. 39 (1972) 521–527] gave a nice explicit formula for the number of such solutions when (a1,…,ak)=ti=1 (1≤i≤k). The problem is very well-motivated and has found intriguing applications in several areas of mathematics, computer science, and physics, and there is promise for more applications/implications in these or other directions.
Year
DOI
Venue
2015
10.1016/j.jnt.2016.07.018
Journal of Number Theory
Keywords
DocType
Volume
11D79,11P83,11L03,11A25,42A16
Journal
171
ISSN
Citations 
PageRank 
0022-314X
1
0.35
References 
Authors
0
5
Name
Order
Citations
PageRank
Khodakhast Bibak1136.63
Bruce M. Kapron230826.02
Srinivasan Venkatesh313610.67
Roberto Tauraso420.70
László Tóth531.43