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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

Table of n, a(n) for n=1..105.

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.]

N. J. A. Sloane, Catalog of Toothpick and Cellular Automata Sequences in the OEIS

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

Cf. A139250, A139251, A160410, A161411, A171170.

Sequence in context: A322424 A309198 A256914 * A159957 A053840 A010883

Adjacent sequences:  A171168 A171169 A171170 * A171172 A171173 A171174

KEYWORD

nonn,tabf

AUTHOR

Omar E. Pol, Dec 04 2009

STATUS

approved

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Last modified December 16 00:33 EST 2019. Contains 330013 sequences. (Running on oeis4.)