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 A366113 #25 Oct 04 2023 12:38:30 %S A366113 1,2,1,3,1,2,4,1,2,1,5,1,2,1,3,6,1,2,1,3,1,7,1,2,1,3,1,2,8,1,2,1,3,1, %T A366113 2,4,9,1,2,1,3,1,2,4,1,10,1,2,1,3,1,2,4,1,2,11,1,2,1,3,1,2,4,1,2,1,12, %U A366113 1,2,1,3,1,2,4,1,2,1,5,13,1,2,1,3,1,2,4,1,2,1,5,1,14 %N A366113 A fractal sequence. Pick any term t: exactly one of the t terms following t is larger than t. %C A366113 Starting with a(1) = 1, this is the lexicographically earliest sequence with this property. %C A366113 This is how the sequence was built: %C A366113 1) start with the Natural numbers and increase the gaps between them by one unit (first gap is zero): %C A366113 S = 1,2,_,3,_,_,4,_,_,_,5,_,_,_,_,6,_,_,_,_,_,7,_,_,_,_,_,_,8, … %C A366113 2) fill the empty spaces with the successive _starting_ chunks of the sequence S _itself_: %C A366113 S = 1,2,_,3,_,_,4,_,_,_,5,_,_,_,_,6,_,_,_,_,_,7,_,_,_,_,_,_,8,_, … %C A366113 S = 1,2,1,3,_,_,4,_,_,_,5,_,_,_,_,6,_,_,_,_,_,7,_,_,_,_,_,_,8,_, … %C A366113 S = 1,2,1,3,1,2,4,_,_,_,5,_,_,_,_,6,_,_,_,_,_,7,_,_,_,_,_,_,8,_, … %C A366113 S = 1,2,1,3,1,2,4,1,2,1,5,_,_,_,_,6,_,_,_,_,_,7,_,_,_,_,_,_,8,_, … %C A366113 S = 1,2,1,3,1,2,4,1,2,1,5,1,2,1,3,6,_,_,_,_,_,7,_,_,_,_,_,_,8,_, … %C A366113 S = 1,2,1,3,1,2,4,1,2,1,5,1,2,1,3,6,1,2,1,3,1,7,_,_,_,_,_,_,8,_, … %C A366113 S = 1,2,1,3,1,2,4,1,2,1,5,1,2,1,3,6,1,2,1,3,1,7,1,2,1,3,1,2,8,_, … Etc. %H A366113 Neal Gersh Tolunsky, <a href="/A366113/b366113.txt">Table of n, a(n) for n = 1..10000</a> %e A366113 One term out of 1 following a(1) = 1 is larger than 1: this is 2. %e A366113 One term out of 2 following a(2) = 2 is larger than 2: this is 3. %e A366113 One term out of 1 following a(3) = 1 is larger than 1: this is 2. %e A366113 One term out of 3 following a(4) = 3 is larger than 3: this is 4. %e A366113 One term out of 1 following a(5) = 1 is larger than 1: this is 2. %e A366113 One term out of 2 following a(6) = 2 is larger than 2: this is 4. %e A366113 One term out of 4 following a(7) = 4 is larger than 4: this is 5. %e A366113 One term out of 1 following a(8) = 1 is larger than 1: this is 2. %e A366113 One term out of 2 following a(9) = 2 is larger than 2: this is 5. Etc. %t A366113 k=1;Nest[(k++;Join[#,#[[;;k-2]],{k}])&,{1},13] (* _Giorgos Kalogeropoulos_, Oct 03 2023 *) %Y A366113 Cf. A342042. %K A366113 nonn %O A366113 1,2 %A A366113 _Eric Angelini_, Sep 29 2023 %E A366113 Data corrected by _Giorgos Kalogeropoulos_, Oct 03 2023