A064249 - OEIS

%I #13 Oct 16 2019 11:28:19

%S 2136,6036,7536,11886,17136,18636,21786,24336,27336,27486,28386,28686,

%T 30186,40086,50586,51786,52836,59886,70536,74286,85236,86286,93786,

%U 95286,100986,110586,111636,118386,120936,125736,135636

%N Values of m such that N=(am+1)(bm+1)(cm+1) is a 3-Carmichael number (A087788), where a,b,c = 1,2,25.

%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="/A064249/b064249.txt">Table of n, a(n) for n = 1..10000</a>

%t CarmichaelNbrQ[n_] := ! PrimeQ@ n && Mod[n, CarmichaelLambda@ n] == 1; Select[ Range@ 140000, PrimeQ[# + 1] && PrimeQ[2# + 1] && PrimeQ[25# + 1] && CarmichaelNbrQ[(# + 1)(2# + 1)(25# + 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