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 A135374 #8 Mar 31 2012 10:24:05 %S A135374 1,3,7,15,13,36,127,255,115,123,247,459,1189,13368,23677,35556,11137, %T A135374 122346,224578,145578,112579,133449,367888,11256777,13334455,1366788, %U A135374 112234777,234455568,11356789,112334778,1234446778,2244567999 %N A135374 Mersenne numbers with digits sorted in increasing order and zeros suppressed. %C A135374 This is to A000225 as A078726 is to A000215. a(n) is prime for n = 2, 3, 5, 7, 15, 27, 29 and which other values? %F A135374 a(n) = A004185(2^n - 1) = 2^n - 1, base 10, with digits sorted in increasing order and zeros suppressed. %Y A135374 Cf. A000215, A000225, A004185, A078726. %K A135374 base,nonn %O A135374 1,2 %A A135374 _Jonathan Vos Post_, Dec 09 2007 %E A135374 Offset corrected by _Arkadiusz Wesolowski_, Jun 02 2011