OFFSET
1,1
LINKS
Michel Marcus, Table of n, a(n) for n = 1..1000
MATHEMATICA
Position[Table[Count[Range[0, n - 1], _?(Mod[2^#, n] == # &)], {n, 150}], 0][[All, 1]] (* Michael De Vlieger, Jun 19 2018 *)
PROG
(PARI) isok(n) = sum(s=0, n-1, Mod(2, n)^s == s) == 0; \\ Michel Marcus, Jun 19 2018
CROSSREFS
KEYWORD
nonn
AUTHOR
Jonathan Ayres (jonathan.ayres(AT)btinternet.com), Oct 28 2001
EXTENSIONS
Incorrect term 1 removed by Michel Marcus, Jun 20 2018
STATUS
approved