|
|
A128399
|
|
Numbers k such that k^2 divides 19^k-1.
|
|
18
|
|
|
1, 2, 3, 4, 6, 9, 10, 12, 18, 20, 30, 36, 42, 60, 84, 90, 110, 126, 156, 180, 210, 220, 252, 294, 330, 381, 420, 468, 588, 630, 660, 724, 762, 780, 882, 930, 990, 1092, 1143, 1260, 1332, 1470, 1510, 1524, 1764, 1806, 1830, 1860, 1980, 2028, 2058, 2172, 2286, 2310
(list;
graph;
refs;
listen;
history;
text;
internal format)
|
|
|
OFFSET
|
1,2
|
|
LINKS
|
|
|
MATHEMATICA
|
Join[{1}, Select[Range[3000], PowerMod[19, #, #^2]==1&]] (* Harvey P. Dale, Oct 24 2017 *)
|
|
PROG
|
(PARI) for(k=1, 1e4, if(Mod(19, k^2)^k==1, print1(k", "))) \\ Seiichi Manyama, Mar 25 2020
|
|
CROSSREFS
|
Cf. A127103, A127104, A127105, A127106, A127107, A127102, A127101, A127100, A127092, A128405, A128393, A128394, A128395, A128396, A128397, A128398, A128400, A128401, A128402, A128403, A128404.
|
|
KEYWORD
|
nonn
|
|
AUTHOR
|
|
|
STATUS
|
approved
|
|
|
|