# [seqfan] A071022 etc rule cellular automaton values

Kevin Ryde user42 at zip.com.au
Sat Jan 7 22:48:40 CET 2012

```I'm having trouble understanding the sample values shown in the "rule"
cellular automaton sequences A071022 through A071041 - with the
exception of A071028 which is clear.  Is there a hint as to the table
layout or quite what the values represent?  I see the row length n+1 or
2n+1, but with such a layout I still don't know what I'm looking at!

As an example A071029 rule 22 rows 2n+1 I presume is something like

0,
1, 0, 1,
0, 1, 0, 1, 0,
1, 0, 1, 0, 1, 0, 1,
0, 1, 0, 1, 0, 1, 0, 1, 0,
1, 0, 1, 0, 1, 0, 1, 0, 1, 0, 1,
1, 0, 1, 0, 1, 0, 1, 0, 1, 0, 1, 0, 1,
0, 1, 0, 1, 0, 1, 0, 1, 0, 1, 0, 1, 0, 1, 0,
1, 0, 1, 0, 1, 0, 1, 0, 1, 0, 1, 1, 0, 1, 0, 1, 0,
1, 0, 1, 0, 1, 0, 1, 0, 1, 0, 1, 0, 1, 0, 1, 0, 1, 0

but is that rule 22 style evolution?

A071043 and A071044 describe themselves as the number of 0s and 1s in
the rows of the A071029 triangle.  But they don't seem to correspond to
this layout, but rather to rule 22 starting from a single cell as at
http://mathworld.wolfram.com/ElementaryCellularAutomaton.html

*
***
*   *
*** ***
*       *
***     ***
*   *   *   *
*** *** *** ***
*               *
***             ***
*   *           *   *
*** ***         *** ***
*       *       *       *
***     ***     ***     ***
*   *   *   *   *   *   *   *
*** *** *** *** *** *** *** ***

Other cellular "rule" sequences I've spotted are clear, eg. A070950 is
good.  Some say outright that they start from from a single cell,
eg. A118109 rule 54.  But A071030 also describes itself as rule 54 and
is different.  It's some different starting conditions or encoding or
something is it?

```

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