A194896 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(8).
1, 1, 2, 1, 2, 3, 1, 2, 3, 4, 1, 2, 3, 4, 5, 6, 1, 2, 3, 4, 5, 6, 1, 7, 2, 3, 4, 5, 6, 1, 7, 2, 8, 3, 4, 5, 6, 1, 7, 2, 8, 3, 9, 4, 5, 6, 1, 7, 2, 8, 3, 9, 4, 10, 5, 6, 1, 7, 2, 8, 3, 9, 4, 10, 5, 11, 6, 12, 1, 7, 2, 8, 3, 9, 4, 10, 5, 11, 6, 12, 1, 7, 13, 2, 8, 3, 9, 4, 10, 5, 11, 6, 12, 1, 7
Offset: 1
Examples
First nine rows: 1 1 2 1 2 3 1 2 3 4 1 2 3 4 5 6 1 2 3 4 5 6 1 7 2 3 4 5 6 1 7 2 8 3 4 5 6 1 7 2 8 3 9 4 5
Programs
-
Mathematica
r = -Sqrt[8]; t[n_] := Table[FractionalPart[k*r], {k, 1, n}]; f = Flatten[Table[Flatten[(Position[t[n], #1] &) /@ Sort[t[n], Less]], {n, 1, 20}]] (* A194896 *) TableForm[Table[Flatten[(Position[t[n], #1] &) /@ Sort[t[n], Less]], {n, 1, 15}]] row[n_] := Position[f, n]; u = TableForm[Table[row[n], {n, 1, 20}]] g[n_, k_] := Part[row[n], k]; p = Flatten[Table[g[k, n - k + 1], {n, 1, 13}, {k, 1, n}]] (* A194897 *) q[n_] := Position[p, n]; Flatten[Table[q[n], {n, 1, 80}]] (* A194898 *)
Comments