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 A230329 #26 Dec 06 2014 18:02:58
%S A230329 1,11,31,53,87,131,157,203,237,295,339,387,465,501,523,633,679,755,
%T A230329 833,889,941,1013,1051,1231,1253,1297,1391,1455,1523,1597,1659,1801,
%U A230329 1825,1991,2053,2115,2235,2321,2385,2457,2551,2657,2727,2843,2905
%N A230329 Prime(prime(2*n)) - 2*prime(n).
%C A230329 For n = 12239, 24046, 24140, 24255, ... a(n+1) = a(n), and for n = 2154, 2524, 2810, 3795, ... a(n+1) < a(n). What is the smallest number n such that a(n+2) <= a(n+1) <= a(n)? - _Farideh Firoozbakht_, Oct 18 2013
%C A230329 Using the Prime Number Theorem, prime(n) ~ n log n, the asymptotic behavior is the same as that of A217622, a(n) ~ 2n (log 2n) log(2n log 2n). - _M. F. Hasler_, Oct 19 2013
%F A230329 a(n) = A217622(n) - 2*A000040(n).
%F A230329 a(n) = A217622(n) - A100484(n). - _Omar E. Pol_, Oct 19 2013
%t A230329 Table[Prime[Prime[2n]] - 2Prime[n], {n, 45}]
%o A230329 (PARI) A230329(n)=prime(prime(2*n))-2*prime(n) \\ _M. F. Hasler_, Oct 19 2013
%Y A230329 Cf. A230098, A230285, A066066.
%K A230329 nonn,easy
%O A230329 1,2
%A A230329 _Gerasimov Sergey_, Oct 16 2013
%E A230329 Corrected by _R. J. Mathar_, Oct 18 2013