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 A334233 #11 May 06 2025 11:20:57 %S A334233 0,1,1,2,2,3,3,3,3,4,4,4,4,5,5,6,6,7,7,7,7,6,6,5,5,5,5,6,6,7,7,7,7,8, %T A334233 8,8,8,9,9,10,10,10,10,9,9,8,8,8,8,9,9,10,10,11,11,11,11,12,12,12,12, %U A334233 13,13,14,14,15,15,15,15,14,14,13,13,13,13,14,14 %N A334233 a(n) is the X-coordinate of the point at n steps forward from the origin along the H-order curve defined in A334232; sequence A334234 gives Y-coordinates. %H A334233 Rémy Sigrist, <a href="/A334233/b334233.txt">Table of n, a(n) for n = 0..8193</a> %H A334233 Rémy Sigrist, <a href="/A334233/a334233.gp.txt">PARI program for A334233</a> %H A334233 <a href="/index/Con#coordinates_2D_curves">Index entries for sequences related to coordinates of 2D curves</a> %F A334233 A334232(A334234(n), a(n)) = n. %e A334233 The "forward" branch of H-order curve starting from the origin is as follows: %e A334233 7| 32 %e A334233 | | %e A334233 6| 31 %e A334233 | | %e A334233 5| 26...27 30 %e A334233 | | | | %e A334233 4| 25 28...29 %e A334233 | | %e A334233 3| 8....9 24 21...20 %e A334233 | | | | | | %e A334233 2| 7 10 23...22 19 %e A334233 | | | | %e A334233 1| 2....3 6 11 14...15 18 %e A334233 | | | | | | | | %e A334233 0| 0....1 4....5 12...13 16...17 %e A334233 ---+---------------------------------------- %e A334233 y/x| 0 1 2 3 4 5 6 7 %e A334233 - hence a(9) = a(10) = a(11) = a(12) = 4. %o A334233 (PARI) See Links section. %Y A334233 Cf. A334232, A334234. %K A334233 nonn %O A334233 0,4 %A A334233 _Rémy Sigrist_, Apr 20 2020