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 A064239 Values of m such that N=(am+1)(bm+1)(cm+1) is a 3-Carmichael number (A087788), where a,b,c = 1,2,5. 1

%I

%S 6,36,306,366,546,726,966,1296,2556,3066,3696,3876,4506,6036,6216,

%T 7686,9126,9276,9906,10596,10656,10836,11286,12516,13146,14196,14406,

%U 14736,16266,17106,18216,19416,19476,20406,22146,22806,23766

%N Values of m such that N=(am+1)(bm+1)(cm+1) is a 3-Carmichael number (A087788), where a,b,c = 1,2,5.

%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="/A064239/b064239.txt">Table of n, a(n) for n = 1..10000</a>

%t CarmichaelNbrQ[n_] := ! PrimeQ@ n && Mod[n, CarmichaelLambda@ n] == 1; Select[ Range@ 23800, PrimeQ[# + 1] && PrimeQ[2# + 1] && PrimeQ[5# + 1] &&

%t CarmichaelNbrQ[(# + 1)(2# + 1)(5# + 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

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Last modified September 18 23:16 EDT 2021. Contains 347548 sequences. (Running on oeis4.)