OFFSET
1,1
LINKS
T. Cai, Z. Shen, L. Jia, A congruence involving harmonic sums modulo p^alpha q^beta, arXiv preprint arXiv:1503.02798 [math.NT], 2015.
Yong-Gao Chen, and Xin Tong, On a conjecture of de Koninck, Journal of Number Theory, Volume 154, September 2015, Pages 324-364. See Remark 2 p. 331.
EXAMPLE
The known pairs are (3, 13),(13, 61),(22419767768701, 107419560853453).
CROSSREFS
KEYWORD
nonn,more
AUTHOR
N. J. A. Sloane, Nov 25 2015
STATUS
approved