%I #14 May 21 2013 11:16:15

%S 187,247,4807,12331,21307,32227,50167,61087,62647,82087,89947,101959,

%T 113839,118327,127303,137287,140767,141457,168199,187207,193591,

%U 214819,234247,235807,259207,283943,306907,358423,369799,396727,422719,424057

%N Quasi-Carmichael numbers to base 7: squarefree composites n such that (n,2*3*5) = 1 and prime p|n ==> p-7|n-7.

%C If multiples of 2, 3 and 5 are not excluded, then terms like 15, 55, 715, 759, 1495,... belong to the sequence. - _Giovanni Resta_, May 21 2013

%H Giovanni Resta, <a href="/A029556/b029556.txt">Table of n, a(n) for n = 1..8274</a> (terms < 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[#, 7] &] (* _Giovanni Resta_, May 21 2013 *)

%K nonn

%O 1,1

%A _David W. Wilson_