Ted Dobson, Pablo Spiga. Cayley numbers with arbitrarily many distinct prime factors. Journal of Combinatorial Theory, Series A, 122:301-310, 2017. [doi]
@article{DobsonS17,
title = {Cayley numbers with arbitrarily many distinct prime factors},
author = {Ted Dobson and Pablo Spiga},
year = {2017},
doi = {10.1016/j.jctb.2016.06.005},
url = {http://dx.doi.org/10.1016/j.jctb.2016.06.005},
researchr = {https://researchr.org/publication/DobsonS17},
cites = {0},
citedby = {0},
journal = {Journal of Combinatorial Theory, Series A},
volume = {122},
pages = {301-310},
}