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A194871 Triangular array (and fractal sequence): row n is the permutation of (1,2,...,n) obtained from the increasing ordering of fractional parts {r}, {2r}, ..., {nr}, where r=sqrt(6).

%I A194871 #5 Mar 30 2012 18:57:44
%S A194871 1,1,2,3,1,2,3,1,4,2,5,3,1,4,2,5,3,1,6,4,2,7,5,3,1,6,4,2,7,5,3,1,8,6,
%T A194871 4,2,9,7,5,3,1,8,6,4,2,9,7,5,3,1,10,8,6,4,2,9,7,5,3,1,10,8,6,4,2,11,9,
%U A194871 7,5,3,12,1,10,8,6,4,2,11,9,7,5,3,12,1,10,8,6,4,13,2,11,9,7,5
%N A194871 Triangular array (and fractal sequence):  row n is the permutation of (1,2,...,n) obtained from the increasing ordering of fractional parts {r}, {2r}, ..., {nr}, where r=sqrt(6).
%C A194871 See A194832 for a general discussion.
%e A194871 First nine rows:
%e A194871 1
%e A194871 1 2
%e A194871 3 1 2
%e A194871 3 1 4 2
%e A194871 5 3 1 4 2
%e A194871 5 3 1 6 4 2
%e A194871 7 5 3 1 6 4 2
%e A194871 7 5 3 1 8 6 4 2
%e A194871 9 7 5 3 1 8 6 4 2
%t A194871 r = Sqrt[6];
%t A194871 t[n_] := Table[FractionalPart[k*r], {k, 1, n}];
%t A194871 f = Flatten[Table[Flatten[(Position[t[n], #1] &) /@
%t A194871 Sort[t[n], Less]], {n, 1, 20}]]   (* A194871 *)
%t A194871 TableForm[Table[Flatten[(Position[t[n], #1] &) /@
%t A194871 Sort[t[n], Less]], {n, 1, 15}]]
%t A194871 row[n_] := Position[f, n];
%t A194871 u = TableForm[Table[row[n], {n, 1, 20}]]
%t A194871 g[n_, k_] := Part[row[n], k];
%t A194871 p = Flatten[Table[g[k, n - k + 1], {n, 1, 13},
%t A194871  {k, 1, n}]]   (* A194872 *)
%t A194871 q[n_] := Position[p, n]; Flatten[
%t A194871 Table[q[n], {n, 1, 80}]]   (* A194873 *)
%Y A194871 Cf. A194832, A194872, A194873.
%K A194871 nonn,tabl
%O A194871 1,3
%A A194871 _Clark Kimberling_, Sep 04 2011