OFFSET
1,2
LINKS
Seiichi Manyama, Table of n, a(n) for n = 1..100
MATHEMATICA
Select[Range[15*10^5], PowerMod[10, #, #]==#-1&] (* Harvey P. Dale, Oct 01 2017 *)
CROSSREFS
KEYWORD
nonn
AUTHOR
EXTENSIONS
Corrected by T. D. Noe, Oct 31 2006
STATUS
approved