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 A195111 #6 Mar 30 2012 18:57:44 %S A195111 1,3,2,6,4,5,10,8,9,7,15,13,14,11,12,21,19,20,16,17,18,28,26,27,23,24, %T A195111 25,22,36,34,35,31,32,33,29,30,45,43,44,40,41,42,37,38,39,55,53,54,50, %U A195111 51,52,46,47,48,49,66,64,65,61,62,63,57,58,59,60,56,78,76,77 %N A195111 Interspersion fractally induced by the fractal sequence A002260. %C A195111 See A194959 for a discussion of fractalization and the interspersion fractally induced by a sequence. %C A195111 Every pair of rows eventually intersperse. As a sequence, A194111 is a permutation of the positive integers, with inverse A195129. %C A195111 The sequence A002260 is the fractal sequence obtained by concatenating the segments 1; 12; 123; 1234; 12345;... %e A195111 Northwest corner: %e A195111 1...3...6...10..15..21..28..36..45 %e A195111 2...4...8...13..19..26..34..43..53 %e A195111 5...9...14..20..27..35..44..54..65 %e A195111 7...11..16..23..31..40..50..61..73 %e A195111 12..17..24..32..41..51..62..74..87 %t A195111 j[n_] := Table[k, {k, 1, n}]; t[1] = j[1]; %t A195111 t[n_] := Join[t[n - 1], j[n]] (* A002260 *) %t A195111 t[12] %t A195111 p[n_] := t[20][[n]] %t A195111 g[1] = {1}; g[n_] := Insert[g[n - 1], n, p[n]] %t A195111 f[1] = g[1]; f[n_] := Join[f[n - 1], g[n]] %t A195111 f[20] (* A195110 *) %t A195111 row[n_] := Position[f[30], n]; %t A195111 u = TableForm[Table[row[n], {n, 1, 5}]] %t A195111 v[n_, k_] := Part[row[n], k]; %t A195111 w = Flatten[Table[v[k, n - k + 1], {n, 1, 13}, %t A195111 {k, 1, n}]] (* A195111 *) %t A195111 q[n_] := Position[w, n]; Flatten[Table[q[n], %t A195111 {n, 1, 80}]] (* A195112 *) %Y A195111 Cf. A194959, A002260, A195110, A195112. %K A195111 nonn,tabl %O A195111 1,2 %A A195111 _Clark Kimberling_, Sep 09 2011