OFFSET
1,2
LINKS
Seiichi Manyama, Table of n, a(n) for n = 1..10000
MATHEMATICA
Join[{1}, Select[Range[2, 336], PowerMod[19, #, #] == 1 &]] (* Amiram Eldar, May 05 2021 *)
PROG
(PARI) for(k=1, 1e3, if(Mod(19, k)^k==1, print1(k", ")))
CROSSREFS
KEYWORD
nonn
AUTHOR
Seiichi Manyama, Mar 25 2020
STATUS
approved