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%I #15 May 21 2013 11:14:14
%S 165,357,1885,2397,3965,9447,11877,30597,37245,49657,57405,73437,
%T 75517,76857,106485,127677,146605,155397,187485,211117,223197,223737,
%U 301597,304917,312477,378397,406077,413445,460317,543197,728637,737877,765697
%N Quasi-Carmichael numbers to base -3: squarefree composites n such that for every prime p that divides n, p+3 divides n+3.
%D J.-M. De Koninck, Ces nombres qui nous fascinent, Entry 165, p. 53, Ellipses, Paris 2008.
%H Giovanni Resta, <a href="/A029563/b029563.txt">Table of n, a(n) for n = 1..2693</a> (terms < 10^12)
%H <a href="/index/Ca#Carmichael">Index entries for sequences related to Carmichael numbers.</a>
%t qcp[n_, d_] := Block[{p, e}, {p, e} = Transpose@FactorInteger@n;
%t Length[p] > 1 && Max[e] == 1 && And @@ IntegerQ /@ ((n + d)/(p + d))]; Select[Range[10^6], qcp[#, 3] &] (* _Giovanni Resta_, May 21 2013 *)
%K nonn
%O 1,1
%A _David W. Wilson_