OFFSET
1,1
LINKS
Amiram Eldar, Table of n, a(n) for n = 1..10000
John H. Castillo and Jhony Fernando Caranguay Mainguez, The set of k-units modulo n, arXiv:1708.06812 [math.NT], 2017.
Eric Weisstein's World of Mathematics, Knödel Numbers
MATHEMATICA
Select[Range[10, 2500, 5], Divisible[# - 5, CarmichaelLambda[#]]&] (* Jean-François Alcover, Mar 01 2018 *)
CROSSREFS
KEYWORD
nonn
AUTHOR
STATUS
approved