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 A367914 #21 Jan 20 2024 09:12:54 %S A367914 1,4,3,4,3,2,3,2,1,2,1,2,1,4,1,4,1,4,3,4,3,4,3,4,3,2,3,2,3,2,3,2,1,2, %T A367914 1,2,1,2,1,2,1,4,1,4,1,4,1,4,1,4,3,4,3,4,3,4,3,4,3,4,3,2,3,2,3,2,3,2, %U A367914 3,2,3,2,1,2,1,2,1,2,1,2,1,2,1,2,1,4,1,4,1,4,1,4,1,4 %N A367914 Movement sequence in the counter-clockwise undulating spiral, whereby 1, 2, 3, 4 represent moves to the right, down, left and up. %C A367914 y ^ %C A367914 | %C A367914 4 | 2---3 %C A367914 | | | %C A367914 3 | 2---3 4---3 %C A367914 | | | %C A367914 2 | 2---3 2---3 4---3 %C A367914 | | | | | %C A367914 1 | 2---3 2---3 4---3 4---3 %C A367914 | | | | | %C A367914 0 | 1---2 1---2 1---4 1---4 %C A367914 | | | | | %C A367914 -1 | 1---2 1-- 2 1---4 1---4 %C A367914 | | | | | %C A367914 -2 | 1---2 1---4 1---4 %C A367914 | | | %C A367914 -3 | 1---2 1---4 %C A367914 | | | %C A367914 -4 | 1---4 %C A367914 +------------------------------------> %C A367914 -4 -3 -2 -1 0 1 2 3 4 x %F A367914 a(k1)=1 with k1=i^2*8+i*0+2*j+1 with i,j >= 0 and j<=4i. %F A367914 a(k2)=2 with k2=i^2*8+i*12+2*j+6 with i,j >= 0 and j<=4*i+3. %F A367914 a(k3)=3 with k3=i^2*8+i*8+2*j+3 with i,j >= 0 and j<=4*i+2. %F A367914 a(k4)=4 with k4=i^2*8+i*4+2*j+2 with i,j >= 0 and j<=4*i+1. %Y A367914 Cf. A359058, A359216, A359217, A063826. %K A367914 nonn,walk %O A367914 1,2 %A A367914 _Hans G. Oberlack_, Dec 04 2023