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 A087469 #10 May 23 2015 18:46:07 %S A087469 0,1,0,2,1,3,0,2,4,1,3,0,5,2,4,1,6,3,0,5,2,7,4,1,6,3,0,8,5,2,7,4,1,9, %T A087469 6,3,0,8,5,2,10,7,4,1,9,6,3,0,11,8,5,2,10,7,4,1,12,9,6,3,0,11,8,5,2, %U A087469 13,10,7,4,1,12,9,6,3,0,14,11,8,5,2,13,10,7,4,1,15,12,9,6,3,0,14,11,8,5,2,16 %N A087469 a(n) = number of the row (counting from initial row 0) of the array R in A087468 that contains n. %C A087469 A fractal sequence. %H A087469 Clark Kimberling and John E. Brown, <a href="https://cs.uwaterloo.ca/journals/JIS/VOL7/Kimberling/kimber67.html">Partial Complements and Transposable Dispersions</a>, J. Integer Seqs., Vol. 7, 2004. %e A087469 Northwest corner of R: %e A087469 .1 3 7 12 19 %e A087469 .2 5 10 16 24 %e A087469 .4 8 14 21 30 %e A087469 .6 11 18 26 36 %e A087469 .9 15 23 32 43 %e A087469 a(11)=3 because 11 is in row 3. %Y A087469 Cf. A087468, A087470. %K A087469 nonn %O A087469 1,4 %A A087469 _Clark Kimberling_, Sep 09 2003