A195071 Inverse permutation of A194922; every positive integer occurs exactly once.

1, 3, 2, 6, 5, 4, 9, 10, 8, 7, 13, 15, 14, 12, 11, 18, 21, 20, 19, 17, 16, 24, 27, 28, 26, 25, 23, 22, 31, 34, 36, 35, 33, 32, 30, 29, 39, 42, 45, 44, 43, 41, 40, 38, 37, 48, 51, 55, 54, 53, 52, 50, 49, 47, 46, 58, 61, 65, 66, 64, 63, 62, 60, 59, 57, 56, 69, 72, 76

Offset

1,2

Links

G. C. Greubel, Table of n, a(n) for n = 1..5000

Mathematica

r = Sqrt[2]; p[n_] := n - Floor[n/r]
Table[p[n], {n, 1, 90}]  (* A194920 *)
g[1] = {1}; g[n_] := Insert[g[n - 1], n, p[n]]
f[1] = g[1]; f[n_] := Join[f[n - 1], g[n]]
f[20]  (* A194921 *)
row[n_] := Position[f[30], n];
u = TableForm[Table[row[n], {n, 1, 5}]]
v[n_, k_] := Part[row[n], k];
w = Flatten[Table[v[k, n - k + 1], {n, 1, 13},
{k, 1, n}]]  (* A194922 *)
q[n_] := Position[w, n]; Flatten[Table[q[n],
{n, 1, 80}]]   (* A195071 *)

Crossrefs

Cf. A194922, A194921, A194920, A194959.

Sequence in context: A194840 A194860 A194839 * A195081 A120913 A194922

Adjacent sequences: A195068 A195069 A195070 * A195072 A195073 A195074

Keyword

nonn

Author

Clark Kimberling, Sep 08 2011

Status

approved