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Number of exposed toothpick endpoints in the n-th row of the toothpick structure of A229940 (also A229950).
6

%I #11 Nov 16 2013 14:19:43

%S 0,1,2,2,2,2,2,3,3,2,3,4,3,2,3,4,3,3,4,4,3,2,4,6,4,2,3,4,4,4,4,5,4,2,

%T 4,6,4,2,4,6,5,4,4,4,3,2,5,8,5,3,4,4,4,4,5,6,4,2,5,8,5,2,4,6,5,4,4,4,

%U 4,4,6,9,6,2,3,4,4,4,6,8,5,2,5,8,5,2

%N Number of exposed toothpick endpoints in the n-th row of the toothpick structure of A229940 (also A229950).

%C The second bisection gives A000005.

%C For more information see A229940.

%H Omar E. Pol, <a href="http://www.polprimos.com/imagenespub/poldiv13.jpg">Illustration of initial terms of the divisor function (A000005)</a>, see the third picture.

%H N. J. A. Sloane, <a href="/wiki/Catalog_of_Toothpick_and_CA_Sequences_in_OEIS">Catalog of Toothpick and Cellular Automata Sequences in the OEIS</a>

%H <a href="/index/To#toothpick">Index entries for sequences related to toothpick sequences</a>

%e Illustration of initial terms:

%e ---------------------------------------------------

%e A229940 Diagram n a(n) A000005

%e ---------------------------------------------------

%e . 1 0

%e . 2 1 1

%e 1; | 3 2

%e 0; 4 2 2

%e 1; | 5 2

%e 0; 6 2 2

%e 1; | 7 2

%e 0; 8 3 3

%e 1, 1; | | 9 3

%e 0, 1; | 10 2 2

%e 1, 1; | | 11 3

%e 0, 0; 12 4 4

%e 1, 1; | | 13 3

%e 0, 1; | 14 2 2

%e 1, 1; | | 15 3

%e 0, 0; 16 4 4

%e 1, 1; | | 17 3

%e 0, 1; | 18 3 3

%e 1, 1, 1; | | | 19 4

%e 0, 0, 1; | 20 4 4

%e 1, 1, 1; | | | 21 3

%e 0, 1, 1; | | 22 2 2

%e 1, 1, 1; | | | 23 4

%e 0, 0, 0; 24 6 6

%e 1, 1, 1; | | | 25 4

%e 0, 1, 1; | | 26 2 2

%e 1, 1, 1; | | | 27 3

%e 0, 0, 1; | 28 4 4

%e 1, 1, 1; | | | 29 4

%e 0, 1, 0; | 30 4 4

%e 1, 1, 1; | | | 31 4

%e 0, 0, 1; | 32 5 5

%e 1, 1, 1, 1; | | | |

%e ---------------------------------------------------

%Y Cf. A000005, A139250, A139251, A229940, A229950, A229951.

%K nonn

%O 1,3

%A _Omar E. Pol_, Oct 04 2013