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 A067527 #20 May 24 2017 06:46:33
%S A067527 5,6,8,14,16,20,22,26,32,40,46,50,56,70,110,140,260,470,1190,1330
%N A067527 n - 3^k is a prime for all k > 0 such that 3^k < n.
%C A067527 Is the sequence finite?
%C A067527 No other terms below 3^36. - _Max Alekseyev_, Dec 12 2011
%e A067527 40 is a member as 40 - 3 = 37, 40 - 9 = 31, 40 - 27 = 13 are all primes.
%t A067527 A067527 = {}; Do[k = 1; While[p = n - 3^k; p > 0 && PrimeQ[p], k++]; If[p <= 0, AppendTo[A067527, n]], {n, 4, 10000}]; A067527 (* _T. D. Noe_, Feb 20 2005 *)
%Y A067527 Cf. A067526.
%Y A067527 Cf. A039669 (n - 2^k is prime).
%K A067527 nonn,hard,more
%O A067527 1,1
%A A067527 _Amarnath Murthy_, Feb 17 2002
%E A067527 More terms from _Sascha Kurz_, Mar 18 2002
%E A067527 Edited by _Max Alekseyev_, Dec 12 2011