Carmichael numbers in arithmetic progressions
: Matomaki K
Publisher: CAMBRIDGE UNIV PRESS
: 2013
: Journal of the Australian Mathematical Society
: JOURNAL OF THE AUSTRALIAN MATHEMATICAL SOCIETY
: J AUST MATH SOC
: 2
: 94
: 2
: 268
: 275
: 8
: 1446-7887
DOI: https://doi.org/10.1017/S1446788712000547
We prove that when (a, m) = 1 and a is a quadratic residue mod m, there are infinitely many Carmichael numbers in the arithmetic progression a mod m. Indeed the number of them up to x is at least x^(1/5) when x is large enough (depending on m).