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Quasi-Carmichael numbers to base 6: squarefree composites n such that (n,2*3*5) = 1 and prime p|n ==> p-6|n-6.
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%I #14 May 21 2013 11:15:52

%S 13481,484133,554749,618481,3898571,13810481,17710811,27754681,

%T 68170091,113268161,132484891,488476513,562612331,629962801,944029141,

%U 1759856741,2024292991,2406729331,2491302281,2740377481,2781100471,3089281663

%N Quasi-Carmichael numbers to base 6: squarefree composites n such that (n,2*3*5) = 1 and prime p|n ==> p-6|n-6.

%C If multiples of 2, 3 and 5 are not excluded, then terms like 6, 10, 14, 15, 21, 30, 35,... belong to the sequence. - _Giovanni Resta_, May 21 2013

%H Giovanni Resta, <a href="/A029557/b029557.txt">Table of n, a(n) for n = 1..113</a> (terms < 5*10^12)

%H <a href="/index/Ca#Carmichael">Index entries for sequences related to Carmichael numbers.</a>

%t qcm[n_, d_] := Block[{p, e}, {p, e} = Transpose@FactorInteger@n; Length[p] > 1 && Max[e] == 1 && d < Min[p] && And @@ IntegerQ /@ ((n - d)/(p - d))]; Select[Range[10^6], qcm[#, 6] &] (* _Giovanni Resta_, May 21 2013 *)

%K nonn

%O 1,1

%A _David W. Wilson_