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%I #13 Oct 16 2019 11:27:54
%S 30,228,498,1398,1758,2028,2280,3180,4800,5430,6150,6420,6708,7950,
%T 8688,9930,11838,13728,16518,16878,17490,19488,26040,28200,30108,
%U 30468,33528,33870,34140,34500,35490,35670,38298,38820,39900,40350
%N Values of m such that N=(am+1)(bm+1)(cm+1) is a 3-Carmichael number (A087788), where a,b,c = 1,2,9.
%C am+1, bm+1, cm+1 are primes and am | (N-1), bm | (N-1), cm |(N-1).
%D Harvey Dubner (harvey(AT)dubner.com), personal communication, Jun 27 2001.
%H Amiram Eldar, <a href="/A064241/b064241.txt">Table of n, a(n) for n = 1..10000</a>
%t CarmichaelNbrQ[n_] := ! PrimeQ@ n && Mod[n, CarmichaelLambda@ n] == 1; Select[ Range@ 42000, PrimeQ[# + 1] && PrimeQ[2# + 1] && PrimeQ[9# + 1] && CarmichaelNbrQ[(# + 1)(2# + 1)(9# + 1)] &] (* _Robert G. Wilson v_, Aug 23 2012 *)
%Y Cf. A087788.
%K nonn
%O 1,1
%A _N. J. A. Sloane_, Sep 23 2001
%E Offset corrected by _Amiram Eldar_, Oct 16 2019