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A177919
Numbers k such that k^3 divides 19^(k^2) - 1.
15
1, 2, 3, 4, 6, 9, 10, 12, 18, 20, 30, 36, 42, 60, 68, 78, 84, 90, 110, 126, 156, 180, 204, 210, 220, 222, 234, 252, 294, 330, 340, 362, 381, 390, 420, 438, 444, 468, 546, 588, 612, 630, 654, 660, 666, 724, 762, 780, 820, 876, 882, 930, 990, 1010, 1014, 1020
OFFSET
1,2
LINKS
MATHEMATICA
Select[ Range[10^4], Mod[ PowerMod[ 19, #^2, #^3 ] - 1, #^3 ] == 0 &]
KEYWORD
nonn
AUTHOR
Alexander Adamchuk, May 14 2010
STATUS
approved