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%I #39 Jun 21 2022 04:23:18
%S 2,3,5,6,8,15,16,17,23,25,26,27,28,33,34,35,37,38,40,44,49,50,52,54,
%T 56,57,59,60,65,67,70,73,75,76,91,94,97,99,101,110,112,115,118,121,
%U 122,123,127,128,129,132,136,143,149,154,155,157,161,162,172,174
%N Values of k such that there are exactly two primes between 10k and 10k + 9.
%H V. Raman, <a href="/A216293/b216293.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
%e 23 is in the sequence because between 230 and 239 there are exactly two primes: 233 and 239. [_Bruno Berselli_, Sep 04 2012]
%t t = {}; Do[ps = Select[Range[10*n, 10*n + 9], PrimeQ]; If[Length[ps] == 2, AppendTo[t, n]], {n, 0, 229}]; t (* _T. D. Noe_, Sep 03 2012 *)
%t Select[Range[200],Count[Range[10#,10#+9],_?PrimeQ]==2&] (* _Harvey P. Dale_, Jan 19 2017 *)
%o (Magma) [n: n in [1..200] | #PrimesInInterval(10*n, 10*n+9) eq 2]; // _Bruno Berselli_, Sep 04 2012
%Y Cf. A032352, A007811, A078494, A216292.
%K nonn
%O 1,1
%A _V. Raman_, Sep 03 2012
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