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%I #24 Sep 08 2022 08:46:03
%S 22,61,85,142,166,169,178,199,268,316,415,451,478,541,682,775,787,862,
%T 1045,1111,1237,1387,1618,1720,1738,2014,2035,2074,2131,2215,2305,
%U 2362,2410,2710,2773,2938,3013,3055,3271,3334,3361,3412,3652,4012,4042,4069
%N Numbers k such that 10k+1 is composite but 10k+3, 10k+7, 10k+9 are all prime.
%H V. Raman, <a href="/A216299/b216299.txt">Table of n, a(n) for n = 1..10000</a>
%F a(n) >> n log^3 n. - _Charles R Greathouse IV_, Sep 07 2012
%t t = {}; Do[ps = Select[Range[10*n, 10*n + 9], PrimeQ]; If[ps == {10*n + 3, 10*n + 7, 10*n + 9}, AppendTo[t, n]], {n, 0, 4978}]; t (* _T. D. Noe_, Sep 03 2012 *)
%t Select[Range[4100],CompositeQ[10#+1]&&AllTrue[10#+{3,7,9},PrimeQ]&] (* Requires Mathematica version 10 or later *) (* _Harvey P. Dale_, Sep 14 2019 *)
%o (Magma) [k:k in [1..4100]| not IsPrime(10*k+1) and forall{m:m in [3,7,9]| IsPrime(10*k+m)}]; // _Marius A. Burtea_, Feb 02 2020
%Y Cf. A032352, A007811, A078494.
%K nonn
%O 1,1
%A _V. Raman_, Sep 03 2012
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