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 A186312 #11 May 24 2012 17:02:33 %S A186312 11,59,101,149,179,227,569,599,641,809,821,1019,1049,1061,1289,1319, %T A186312 1427,1451,1481,1667,1787,1871,1877,1931,1949,2081,2129,2237,2657, %U A186312 2687,2711,2999,3251,3257,3299,3359,3461,3467,3527,3539,3767,3917,4001,4019,4091 %N A186312 There appear to be at least n lower twin primes between x/2 and x for all x >= a(n). %C A186312 The name says "appear" because this sequence assumes that the twin prime conjecture is true. Note that every term is also a lower twin prime. This sequence for lower twin primes is like the Ramanujan primes (A104272) for the sequence of prime numbers. However, in this case, we do not know if there are an infinite number of twin primes. It appears that A001359(2n) < a(n) < A001359(4n). %H A186312 T. D. Noe, <a href="/A186312/b186312.txt">Table of n, a(n) for n = 1..1000</a> %Y A186312 Cf. A001359 (lower twin primes), A088018 (counts the lower twin primes between n-1 and 2(n-1)). %K A186312 nonn %O A186312 1,1 %A A186312 _T. D. Noe_, Feb 17 2011