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 A373255 #8 May 31 2024 22:08:09 %S A373255 2,3,4,5,7,10,11,12,13,17,19,21,22,23,25,29,30,31,34,37,39,41,43,46, %T A373255 47,48,53,55,57,58,59,61,66,67,71,73,75,79,82,83,84,85,89,93,94,97, %U A373255 101,102,103,106,107,109,111,113,115,118,120,121,127,128,129,131,137,138,139,142,145,147,149,151,156,157,163 %N A373255 Numbers k for which A003415(k) == +1 (mod 3), where A003415 is the arithmetic derivative. %H A373255 Antti Karttunen, <a href="/A373255/b373255.txt">Table of n, a(n) for n = 1..10000</a> %o A373255 (PARI) isA373255 = A373254; %Y A373255 Positions of +1's in A373253. %Y A373255 Cf. A000040 (subsequence), A003415, A373254 (characteristic function). %K A373255 nonn %O A373255 1,1 %A A373255 _Antti Karttunen_, May 31 2024