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Values of n such that N=(an+1)(bn+1)(cn+1) is a 3-Carmichael number (A087788), where a,b,c = 1,2,33.
1

%I #12 Oct 17 2019 06:07:24

%S 576,1170,2556,6120,20706,23676,29220,29286,32586,39450,46380,46446,

%T 50076,52386,58920,63210,65256,65850,69876,74100,77796,93240,107826,

%U 113370,114030,116340,127296,128220,129606,130530,140826,141156,149340,170196,174090,177126,178446

%N Values of n such that N=(an+1)(bn+1)(cn+1) is a 3-Carmichael number (A087788), where a,b,c = 1,2,33.

%C an+1, bn+1, cn+1 are primes and an | (N-1), bn | (N-1), cn |(N-1).

%D Harvey Dubner (harvey(AT)dubner.com), personal communication, Jun 27 2001.

%H Amiram Eldar, <a href="/A064253/b064253.txt">Table of n, a(n) for n = 1..10000</a>

%t carmQ[n_] := CompositeQ[n] && Divisible[n - 1, CarmichaelLambda[n]]; Select[Range[10^5], AllTrue[(v = {1, 2, 33}*# + 1), PrimeQ] && carmQ[Times @@ v] &] (* _Amiram Eldar_, Oct 17 2019 *)

%Y Cf. A087788.

%K nonn

%O 1,1

%A _N. J. A. Sloane_, Sep 23 2001

%E More terms from _Amiram Eldar_, Oct 17 2019