login
The OEIS is supported by the many generous donors to the OEIS Foundation.

 

Logo
Hints
(Greetings from The On-Line Encyclopedia of Integer Sequences!)
A195083 Interspersion fractally induced by (1+[2n/3]), where [ ] = floor; a rectangular array, by antidiagonals. 3

%I #5 Mar 30 2012 18:57:44

%S 1,2,3,4,5,6,7,8,10,9,11,12,15,13,14,16,17,21,18,19,20,22,23,28,24,25,

%T 27,26,29,30,36,31,32,35,33,34,37,38,45,39,40,44,41,42,43,46,47,55,48,

%U 49,54,50,51,53,52,56,57,66,58,59,65,60,61,64,62,63,67,68,78

%N Interspersion fractally induced by (1+[2n/3]), where [ ] = floor; a rectangular array, by antidiagonals.

%C See A194959 for a discussion of fractalization and the interspersion fractally induced by a sequence. Every pair of rows eventually intersperse. As a sequence, A194983 is a permutation of the positive integers, with inverse A195096.

%e Northwest corner:

%e 1...2...4...7...11..16

%e 3...5...8...12..17..23

%e 6...10..15..21..28..36

%e 9...13..18..24..31..39

%e 14..19..25..32..40..49

%t r = 2/3; p[n_] := 1 + Floor[n*r]

%t Table[p[n], {n, 1, 90}] (* ess A004396 *)

%t g[1] = {1}; g[n_] := Insert[g[n - 1], n, p[n]]

%t f[1] = g[1]; f[n_] := Join[f[n - 1], g[n]]

%t f[20] (* A195082 *)

%t row[n_] := Position[f[30], n];

%t u = TableForm[Table[row[n], {n, 1, 5}]]

%t v[n_, k_] := Part[row[n], k];

%t w = Flatten[Table[v[k, n - k + 1], {n, 1, 13}, ]

%t {k, 1, n}]] (* A195083 *)

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

%t {n, 1, 80}]] (* A195096 *)

%Y Cf. A004396, A195083, A195096.

%K nonn,tabl

%O 1,2

%A _Clark Kimberling_, Sep 08 2011

Lookup | Welcome | Wiki | Register | Music | Plot 2 | Demos | Index | Browse | More | WebCam
Contribute new seq. or comment | Format | Style Sheet | Transforms | Superseeker | Recents
The OEIS Community | Maintained by The OEIS Foundation Inc.

License Agreements, Terms of Use, Privacy Policy. .

Last modified April 24 02:28 EDT 2024. Contains 371917 sequences. (Running on oeis4.)