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A248513 Rectangular array by antidiagonals: the dispersion of A181155 ("odious numbers"). 4
1, 2, 4, 3, 8, 6, 5, 15, 12, 7, 9, 29, 23, 14, 10, 17, 57, 45, 27, 20, 11, 33, 113, 89, 53, 39, 22, 13, 65, 225, 177, 105, 77, 43, 26, 16, 129, 449, 353, 209, 153, 85, 51, 32, 18, 257, 897, 705, 417, 305, 169, 101, 63, 36, 19, 513, 1793, 1409, 833, 609, 337 (list; table; graph; refs; listen; history; text; internal format)
OFFSET

1,2

COMMENTS

Background discussion: Suppose that s is an increasing sequence of positive integers, that the complement t of s is infinite, and that t(1) = 1. The dispersion of s is the array D whose n-th row is (t(n), s(t(n)), s(s(t(n)), s(s(s(t(n)))), ...).  Every positive integer occurs exactly once in D, so that, as a sequence, D is a permutation of the positive integers. The sequence u given by u(n) = (number of the row of D that contains n) is a fractal sequence, as in A248514.

The n-th term of column 1 is A001969(n) + 1, where A001969 are the "evil numbers".

REFERENCES

Clark Kimberling, Fractal sequences and interspersions, Ars Combinatoria 45 (1997) 157-168.

LINKS

Clark Kimberling, Antidiagonals n = 1..60, flattened

Clark Kimberling, Interspersions and dispersions, Proceedings of the American Mathematical Society, 117 (1993) 313-321.

EXAMPLE

Northwest corner:

1 ... 2 ... 3 ... 5 ... 9 .... 17 ... 33

4 ... 8 ... 15 .. 29 .. 57 ... 113 .. 225

6 ... 12 .. 23 .. 45 .. 89 ... 177 .. 353

7 ... 14 .. 27 .. 53 .. 105 .. 209 .. 417

10 .. 20 .. 39 .. 77 .. 153 .. 305 .. 609

MATHEMATICA

r = 40; r1 = 10; (* r = # rows of T, r1 = # rows to show *);

c = 40; c1 = 12; (* c = # cols of T, c1 = # cols to show *);

x = GoldenRatio;

s[n_] := s[n] = If[n < 1, 0, 2 n - Mod[Total[IntegerDigits[n - 1, 2]], 2]];

mex[list_] := NestWhile[#1 + 1 &, 1, Union[list][[#1]] <= #1 &, 1,   Length[Union[list]]]; rows = {NestList[s, 1, c]};

Do[rows = Append[rows, NestList[s, mex[Flatten[rows]], r]], {r}];

t[i_, j_] := rows[[i, j]]; TableForm[Table[t[i, j], {i, 1, r1}, {j, 1, c1}]]

u = Flatten[Table[t[k, n - k + 1], {n, 1, c1}, {k, 1, n}]] (* A248513 *)

row[i_] := row[i] = Table[t[i, j], {j, 1, c}]

f[n_] := Select[Range[r], MemberQ[row[#], n] &]

v = Flatten[Table[f[n], {n, 1, 200}]]  (* A248514 *)

CROSSREFS

Cf. A248514.

Sequence in context: A232563 A048672 A277517 * A266414 A245613 A260431

Adjacent sequences:  A248510 A248511 A248512 * A248514 A248515 A248516

KEYWORD

nonn,tabl,easy

AUTHOR

Clark Kimberling, Oct 08 2014

STATUS

approved

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Last modified May 29 21:28 EDT 2017. Contains 287257 sequences.