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A221146 Table read by antidiagonals: (m+n) - (m XOR n). 2
0, 0, 0, 0, 2, 0, 0, 0, 0, 0, 0, 2, 4, 2, 0, 0, 0, 4, 4, 0, 0, 0, 2, 0, 6, 0, 2, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 2, 4, 2, 8, 2, 4, 2, 0, 0, 0, 4, 4, 8, 8, 4, 4, 0, 0, 0, 2, 0, 6, 8, 10, 8, 6, 0, 2, 0, 0, 0, 0, 0, 8, 8, 8, 8, 0, 0, 0, 0, 0, 2, 4, 2, 0, 10, 12, 10, 0, 2, 4, 2 (list; table; graph; refs; listen; history; text; internal format)
OFFSET

0,5

COMMENTS

Equals twice A004198.

This sequence is related to two fractals: the Sierpinski gasket fractal and Peano filigree.

For the Sierpinski fractal the procedure is the following:

- write the number stored in the position (i,j) as i+j + d, where d stands for difference.

The array of the differences is

0 0 0 0

0 2 0 2

0 0 4 4

0 2 4 6

If this matrix is represented by colors we obtain the Sierpinski gasket; coordinates (i,j) contain a pixel with the color i XOR j.

If we follow the odd and even numbers of the XOR table we obtain the Peano curve.

LINKS

Table of n, a(n) for n=0..89.

EXAMPLE

Table begins:

0   0   0   0   0   0   0   0   0   0   0   0   0   0   0   0 ...

0   2   0   2   0   2   0   2   0   2   0   2   0   2   0   2 ...

0   0   4   4   0   0   4   4   0   0   4   4   0   0   4   4 ...

0   2   4   6   0   2   4   6   0   2   4   6   0   2   4   6 ...

0   0   0   0   8   8   8   8   0   0   0   0   8   8   8   8 ...

0   2   0   2   8  10   8  10   0   2   0   2   8  10   8  10 ...

0   0   4   4   8   8  12  12   0   0   4   4   8   8  12  12 ...

0   2   4   6   8  10  12  14   0   2   4   6   8  10  12  14 ...

0   0   0   0   0   0   0   0  16  16  16  16  16  16  16  16 ...

0   2   0   2   0   2   0   2  16  18  16  18  16  18  16  18 ...

0   0   4   4   0   0   4   4  16  16  20  20  16  16  20  20 ...

0   2   4   6   0   2   4   6  16  18  20  22  16  18  20  22 ...

0   0   0   0   8   8   8   8  16  16  16  16  24  24  24  24 ...

0   2   0   2   8  10   8  10  16  18  16  18  24  26  24  26 ...

0   0   4   4   8   8  12  12  16  16  20  20  24  24  28  28 ...

0   2   4   6   8  10  12  14  16  18  20  22  24  26  28  30 ...

...

CROSSREFS

Cf. A003987, A004198.

Sequence in context: A082523 A186034 A280843 * A083935 A053201 A028605

Adjacent sequences:  A221143 A221144 A221145 * A221147 A221148 A221149

KEYWORD

nonn,tabl

AUTHOR

BOCUT Adrian Sebastian, Dec 12 2012

EXTENSIONS

Edited by N. J. A. Sloane, Jan 03 2013

STATUS

approved

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Last modified July 27 15:29 EDT 2021. Contains 346307 sequences. (Running on oeis4.)