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A065702
Values of m such that N = (am+1)(bm+1)(cm+1) is a 3-Carmichael number (A087788), where a,b,c = 1,2,69.
3
378, 1068, 24390, 29220, 32118, 56130, 70620, 74760, 77658, 82350, 96978, 100980, 110640, 114228, 132858, 152040, 177018, 183090, 186678, 214830, 253608, 282588, 290040, 319158, 342480, 345378, 374358, 388710, 406788, 418380, 428040, 442530, 463230, 463920, 477720
OFFSET
1,1
LINKS
FORMULA
am+1, bm+1, cm+1 are primes and am|(N-1), bm|(N-1), cm|(N-1).
MATHEMATICA
CarmichaelNbrQ[n_] := ! PrimeQ@ n && Mod[n, CarmichaelLambda@ n] == 1; Select[ Range@ 500000, PrimeQ[# + 1] && PrimeQ[2# + 1] && PrimeQ[69# + 1] && CarmichaelNbrQ[(# + 1)(2# + 1)(69# + 1)] &] (* Robert G. Wilson v, Aug 23 2012 *)
CROSSREFS
KEYWORD
nonn
AUTHOR
Harvey Dubner (harvey(AT)dubner.com), Nov 14 2001
STATUS
approved