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Values of k such that 10*k+3 and 10*k+7 alone are prime between 10*k and 10*k+9.
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%I #13 Jul 20 2021 14:34:46

%S 16,67,121,220,229,247,283,295,334,361,379,394,481,592,604,673,724,

%T 757,760,772,793,844,880,913,988,1024,1066,1108,1144,1159,1186,1192,

%U 1234,1243,1303,1318,1396,1417,1453,1465,1471,1501,1507,1537,1549,1660,1762,1858

%N Values of k such that 10*k+3 and 10*k+7 alone are prime between 10*k and 10*k+9.

%H V. Raman, <a href="/A216306/b216306.txt">Table of n, a(n) for n = 1..10000</a>

%F a(n) >> n log^2 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}, AppendTo[t, n]], {n, 0, 2476}]; t (* _T. D. Noe_, Sep 04 2012 *)

%t Select[Range[2000],Boole[PrimeQ[10#+{1,3,7,9}]]=={0,1,1,0}&] (* _Harvey P. Dale_, Jul 20 2021 *)

%Y Cf. A032352, A007811, A078494.

%K nonn

%O 1,1

%A _V. Raman_, Sep 03 2012