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 A044229 #11 Sep 03 2025 09:38:22 %S A044229 42,106,170,234,298,336,362,426,490,554,618,682,746,810,848,874,938, %T A044229 1002,1066,1130,1194,1258,1322,1360,1386,1450,1514,1578,1642,1706, %U A044229 1770,1834,1872,1898,1962,2026,2090,2154,2218,2282,2346 %N A044229 Numbers k such that string 5,2 occurs in the base 8 representation of k but not of k-1. %H A044229 Paolo Xausa, <a href="/A044229/b044229.txt">Table of n, a(n) for n = 1..10000</a> %t A044229 A044229Q[k_] := StringContainsQ[IntegerString[k, 8], "52"] && StringFreeQ[IntegerString[k - 1, 8], "52"]; %t A044229 Select[Range[5000], A044229Q] (* _Paolo Xausa_, Sep 03 2025 *) %Y A044229 Cf. A007094. %K A044229 nonn,base,changed %O A044229 1,1 %A A044229 _Clark Kimberling_