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A194981 Interspersion fractally induced by A194979, a rectangular array, by antidiagonals. 7
1, 2, 3, 4, 6, 5, 7, 10, 8, 9, 11, 15, 12, 14, 13, 16, 21, 17, 20, 18, 19, 22, 28, 23, 27, 24, 25, 26, 29, 36, 30, 35, 31, 32, 34, 33, 37, 45, 38, 44, 39, 40, 43, 41, 42, 46, 55, 47, 54, 48, 49, 53, 50, 52, 51, 56, 66, 57, 65, 58, 59, 64, 60, 63, 61, 62, 67, 78, 68 (list; table; graph; refs; listen; history; text; internal format)
OFFSET

1,2

COMMENTS

See A194959 for a discussion of fractalization and the interspersion fractally induced by a sequence.  Every pair of rows eventually intersperse.  As a sequence, A194981 is a permutation of the positive integers, with inverse A194982.

LINKS

Table of n, a(n) for n=1..69.

EXAMPLE

Northwest corner:

1...2...4...7...11..16..22

3...6...10..15..21..28..36

5...8...12..17..23..30..38

9...14..20..27..35..44..54

13..18..24..31..39..48..58

MATHEMATICA

r = Sqrt[3]; p[n_] := 1 + Floor[n/r]

Table[p[n], {n, 1, 90}]  (* A194979 = 1+ A097337 *)

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] (* A194980 *)

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}]]  (* A194981 *)

q[n_] := Position[w, n]; Flatten[Table[q[n],

{n, 1, 80}]]  (* A194982 *)

CROSSREFS

Cf. A194959, A019480, A194982.

Sequence in context: A194982 A064578 A194969 * A057027 A090894 A175004

Adjacent sequences:  A194978 A194979 A194980 * A194982 A194983 A194984

KEYWORD

nonn,tabl

AUTHOR

Clark Kimberling, Sep 07 2011

STATUS

approved

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Last modified May 7 02:20 EDT 2021. Contains 343636 sequences. (Running on oeis4.)