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A171171 Corner sequence (starting each round with the corner (SE): 1,2,3). 1
1, 2, 3, 4, 1, 2, 3, 2, 3, 4, 3, 4, 1, 4, 1, 2, 1, 2, 3, 2, 3, 4, 3, 4, 1, 4, 1, 2, 1, 2, 3, 2, 3, 4, 1, 2, 3, 2, 3, 4, 3, 4, 1, 2, 3, 4, 3, 4, 1, 4, 1, 2, 3, 4, 1, 4, 1, 2, 1, 2, 3, 4, 1, 2, 1, 2, 3, 2, 3, 4, 3, 4, 1, 4, 1, 2, 1, 2, 3, 2, 3, 4, 1, 2, 3, 2, 3, 4, 3, 4, 1, 2, 3, 4, 3, 4, 1, 4, 1, 2, 3, 4, 1, 4, 1 (list; graph; refs; listen; history; text; internal format)
OFFSET
1,2
COMMENTS
See A161411, which is the main entry for this sequence.
See also A171170 for another version.
LINKS
David Applegate, Omar E. Pol and N. J. A. Sloane, The Toothpick Sequence and Other Sequences from Cellular Automata, Congressus Numerantium, Vol. 206 (2010), 157-191. [There is a typo in Theorem 6: (13) should read u(n) = 4.3^(wt(n-1)-1) for n >= 2.]
EXAMPLE
================
.......41.......
.......32.......
================
......4141......
......3..2......
......4..1......
......3232......
================
.....41..41.....
.....3....2.....
................
................
.....4....1.....
.....32..32.....
================
....41414141....
....3..23..2....
....4......1....
....32....32....
....41....41....
....3......2....
....4..14..1....
....32323232....
================
...41......41...
...3........2...
................
................
................
................
................
................
................
...4........1...
...32......32...
================
And so on.
Triangle begins:
1,2,3,4;
1,2,3, 2,3,4, 3,4,1, 4,1,2;
1,2,3, 2,3,4, 3,4,1, 4,1,2;
1,2,3,2,3,4,1,2,3, 2,3,4,3,4,1,2,3,4, 3,4,1,4,1,2,3,4,1, 4,1,2,1,2,3,4,1,2;
1,2,3, 2,3,4, 3,4,1, 4,1,2;
1,2,3,2,3,4,1,2,3, 2,3,4,3,4,1,2,3,4, 3,4,1,4,1,2,3,4,1, 4,1,2,1,2,3,4,1,2;
Contribution from Omar E. Pol, Dec 09 2009: (Start)
Illustration for n = 1..148
================
.41..41..41..41.
.341412..341412.
..3412....3412..
..434141414121..
.43234123412321.
.32.43414121.32.
....32341232....
....41432141....
.41.34323212.41.
.34143214321412.
..343232323212..
..4321....4321..
.432321..432321.
.32..32..32..32.
================
(End)
CROSSREFS
Sequence in context: A322424 A309198 A256914 * A159957 A053840 A010883
KEYWORD
nonn,tabf
AUTHOR
Omar E. Pol, Dec 04 2009
STATUS
approved

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Last modified May 27 11:08 EDT 2024. Contains 372858 sequences. (Running on oeis4.)