This is a front-end for the Online Encyclopedia of Integer Sequences, made by Christian Perfect. The idea is to provide OEIS entries in non-ancient HTML, and then to think about how they're presented visually. The source code is on GitHub.
%I A166307 #24 Aug 28 2018 03:23:21 %S A166307 11,17,29,41,47,59,67,97,107,127,137,149,167,179,197,227,263,281,307, %T A166307 347,367,401,431,461,487,503,521,569,587,617,641,677,719,739,751,769, %U A166307 809,821,853,881,907,937,967,983,1009,1019,1049,1087,1097,1117,1151,1163,1187,1217,1229,1249,1277 %N A166307 The smallest prime in some interval of the form (2*prime(k),2*prime(k+1)) if this interval contains at least 2 primes. %C A166307 These are called "right primes" in A166251. %H A166307 Vincenzo Librandi, <a href="/A166307/b166307.txt">Table of n, a(n) for n = 1..1000</a> %e A166307 For p=29 we have: 2*13 < 29 < 2*17 and interval (26, 29) is free from primes while interval (29, 34) contains a prime. Therefore 29 is in the sequence for k=6. %t A166307 f[n_] := Block[{t = Select[ Table[i, {i, 2 Prime[n], 2 Prime[n + 1]}], PrimeQ]}, If[ Length@ t > 1, t[[1]], 0]]; Rest@ Union@ Array[f, 115] (* _Robert G. Wilson v_, May 08 2011 *) %Y A166307 Cf. A166252, A166251, A164368, A104272, A080359, A164333, A164288, A164294, A164554, A182365. %K A166307 nonn %O A166307 1,1 %A A166307 _Vladimir Shevelev_, Oct 11 2009, Oct 17 2009