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 A023749 #14 Apr 02 2014 06:14:06 %S A023749 0,1,2,3,4,5,6,8,9,10,11,12,13,16,17,18,19,20,24,25,26,27,32,33,34,40, %T A023749 41,48,57,58,59,60,61,62,65,66,67,68,69,73,74,75,76,81,82,83,89,90,97, %U A023749 114,115,116,117,118,122,123,124,125,130,131,132,138,139,146,171 %N A023749 Plaindromes: numbers whose digits in base 7 are in nondecreasing order. %H A023749 Vincenzo Librandi, <a href="/A023749/b023749.txt">Table of n, a(n) for n = 1..4000</a> %t A023749 Select[Range[0,171],LessEqual@@IntegerDigits[#,7]&] (* _Ray Chandler_, Jan 06 2014 *) %K A023749 nonn,base,easy %O A023749 1,3 %A A023749 _Olivier Gérard_