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A055695
Numbers k such that 12^k == -1 (mod k-1).
3
2, 6, 30, 146, 42486, 102966, 597198, 2847366, 7998606, 13133666, 30478158, 67622310, 74476206, 101258190, 105161166, 106364286, 187605438, 230000550, 242915166, 401913582, 406756350, 444314574, 848205078, 899715894, 1508418054, 1575220350, 1578086334, 1691859102
OFFSET
1,1
MATHEMATICA
Do[If[PowerMod[12, n, n-1]==n-2, Print[n]], {n, 2, 10^8}]
CROSSREFS
Sequence in context: A295863 A224530 A120950 * A113593 A122763 A166078
KEYWORD
nonn
AUTHOR
Robert G. Wilson v, Jun 09 2000
EXTENSIONS
Terms a(14) onward from Max Alekseyev, Oct 12 2012
STATUS
approved