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 A194863 #8 Jul 30 2023 03:44:42 %S A194863 1,2,3,5,6,4,8,10,7,9,12,14,11,13,15,18,20,16,19,21,17,24,27,22,25,28, %T A194863 23,26,31,34,29,32,35,30,33,36,40,43,37,41,44,38,42,45,39,49,53,46,50, %U A194863 54,47,51,55,48,52,60,64,57,61,65,58,62,66,59,63,56,71,76,68 %N A194863 Rectangular array, by antidiagonals: row n gives the positions of n in the fractal sequence A194862; an interspersion. %C A194863 For a general discussion, see A194832. %e A194863 Northwest corner: %e A194863 1...2...5...8...12..18 %e A194863 3...6...10..14..20..27 %e A194863 4...7...11..16..22..29 %e A194863 9...13..19..25..32..41 %e A194863 15..21..28..35..44..54 %t A194863 r = (1 + Sqrt[3])/2; %t A194863 t[n_] := Table[FractionalPart[k*r], {k, 1, n}]; %t A194863 f = Flatten[Table[Flatten[(Position[t[n], #1] &) /@ %t A194863 Sort[t[n], Less]], {n, 1, 20}]] (* A194862 *) %t A194863 TableForm[Table[Flatten[(Position[t[n], #1] &) /@ %t A194863 Sort[t[n], Less]], {n, 1, 15}]] %t A194863 row[n_] := Position[f, n]; %t A194863 u = TableForm[Table[row[n], {n, 1, 20}]] %t A194863 g[n_, k_] := Part[row[n], k]; %t A194863 p = Flatten[Table[g[k, n - k + 1], {n, 1, 13}, %t A194863 {k, 1, n}]] (* A194863 *) %t A194863 q[n_] := Position[p, n]; Flatten[Table[q[n], %t A194863 {n, 1, 80}]] (* A194867 *) %Y A194863 Cf. A194832, A194862, A194867. %K A194863 nonn,tabl %O A194863 1,2 %A A194863 _Clark Kimberling_, Sep 04 2011