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%I #16 Aug 01 2023 08:07:47
%S 319,697,767,803,1219,1529,1577,1781,1853,2119,2497,2981,3133,3223,
%T 3587,3649,3707,3743,3809,3949,4061,4393,4747,5161,5249,5321,5401,
%U 5837,5899,5909,5983,5989,6127,6509,6611,6631,6931,7633,7697,8063,8203,8473,8797,8879
%N Semiprimes p1*p2 such that p2>p1 and p2 mod p1 = 7.
%H Harvey P. Dale, <a href="/A064905/b064905.txt">Table of n, a(n) for n = 1..1000</a> (corrected by Sean A. Irvine)
%t m7Q[n_]:=Module[{f=Transpose[FactorInteger[n]][[1]]},Length[f]==2 && Mod[ f[[2]],f[[1]]]==7]; Select[Range[10000], And[m7Q[#], SquareFreeQ[#]] &] (* _Harvey P. Dale_, May 02 2016; corrected by _Michael De Vlieger_, Jul 31 2023 *)
%t nn = 8900; m = 7; Union@ Flatten@ Table[p = Prime[i]; Table[q = Prime[j]; If[Mod[q, p] == m, p q, Nothing], {j, i + 1, PrimePi[nn/p]}], {i, PrimePi[nn]}] (* _Michael De Vlieger_, Jul 31 2023 *)
%Y Cf. A001358 (p2 mod p1 = 0), A064899-A064911.
%K nonn
%O 1,1
%A _Patrick De Geest_, Oct 13 2001
%E Corrected and extended by _Harvey P. Dale_, May 02 2016
%E Original data restored, name clarified, and offset corrected by _Sean A. Irvine_, Jul 31 2023
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