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 A195108 #5 Mar 30 2012 18:57:44 %S A195108 1,2,3,5,6,4,8,10,7,9,13,15,11,14,12,19,21,17,20,18,16,26,28,23,27,24, %T A195108 22,25,34,36,30,35,32,29,33,31,43,45,39,44,41,37,42,40,38,53,55,49,54, %U A195108 51,47,52,50,48,46,64,66,59,65,62,57,63,61,58,56,60,76,78,71 %N A195108 Interspersion fractally induced by A004736. %C A195108 See A194959 for a discussion of fractalization and the interspersion fractally induced by a sequence. %C A195108 The sequence A004736 is the fractal sequence obtained by concatenating the segments 1; 2,1; 3,2,1; 4,3,2,1;... %C A195108 Every pair of rows of A195108 eventually intersperse. %C A195108 As a sequence, A194108 is a permutation of the positive integers, with inverse A195109. %e A195108 Northwest corner: %e A195108 1...2...5...8...13..19..26 %e A195108 3...6...10..15..21..28..36 %e A195108 4...7...11..17..23..30..39 %e A195108 9...14..20..27..35..44..54 %e A195108 12..18..24..32..41..51..62 %t A195108 j[n_] := Table[n + 1 - k, {k, 1, n}]; t[1] = j[1]; %t A195108 t[n_] := Join[t[n - 1], j[n]] (* A004736 *) %t A195108 t[10] %t A195108 p[n_] := t[20][[n]] %t A195108 g[1] = {1}; g[n_] := Insert[g[n - 1], n, p[n]] %t A195108 f[1] = g[1]; f[n_] := Join[f[n - 1], g[n]] %t A195108 f[20] (* A195107 *) %t A195108 row[n_] := Position[f[30], n]; %t A195108 u = TableForm[Table[row[n], {n, 1, 5}]] %t A195108 v[n_, k_] := Part[row[n], k]; %t A195108 w = Flatten[Table[v[k, n - k + 1], {n, 1, 13}, %t A195108 {k, 1, n}]] (* A195108 *) %t A195108 q[n_] := Position[w, n]; Flatten[Table[q[n], %t A195108 {n, 1, 80}]] (* A195109 *) %Y A195108 Cf. A194959, A004736, A195107, A195109. %K A195108 nonn,tabl %O A195108 1,2 %A A195108 _Clark Kimberling_, Sep 09 2011