cp's OEIS Frontend

A229950 Total number of toothpicks after n-th stage in a toothpick structure in which the toothpicks represent the 1's of triangle A229940.

%I A229950 #15 Nov 16 2013 14:20:36
%S A229950 0,0,0,1,1,2,2,3,3,5,6,8,8,10,11,13,13,15,16,19,20,23,25,28,28,31,33,
%T A229950 36,37,40,41,44,45,49,52,56,57,61,64,68,69,73,75,79,81,85,88,92,92,96,
%U A229950 99,104,107,112,115,120,122,127,131,136,137,142,146,151,153
%N A229950 Total number of toothpicks after n-th stage in a toothpick structure in which the toothpicks represent the 1's of triangle A229940.
%C A229950 The toothpick structure has the property that the number of exposed endpoints in the row 2k equals the number of divisors of k, if 1<2k<n, k>=1. See example and Link section.
%H A229950 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 A229950 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 A229950 <a href="/index/To#toothpick">Index entries for sequences related to toothpick sequences</a>
%e A229950 Illustration of initial terms:
%e A229950 ---------------------------------------
%e A229950 n      a(n)       Diagram      A000005
%e A229950 ---------------------------------------
%e A229950 0       0
%e A229950 1       0
%e A229950 2       0                         1
%e A229950 3       1         |
%e A229950 4       1                         2
%e A229950 5       2         |
%e A229950 6       2                         2
%e A229950 7       3         |
%e A229950 8       3                         3
%e A229950 9       5         | |
%e A229950 10      6           |             2
%e A229950 11      8         | |
%e A229950 12      8                         4
%e A229950 13      10        | |
%e A229950 14      11          |             2
%e A229950 15      13        | |
%e A229950 16      13                        4
%e A229950 17      15        | |
%e A229950 18      16          |             3
%e A229950 19      19        | | |
%e A229950 20      20            |           4
%e A229950 21      23        | | |
%e A229950 22      25          | |           2
%e A229950 23      28        | | |
%e A229950 24      28                        6
%e A229950 25      31        | | |
%e A229950 26      33          | |           2
%e A229950 27      36        | | |
%e A229950 28      37            |           4
%e A229950 29      40        | | |
%e A229950 30      41          |             4
%e A229950 31      44        | | |
%e A229950 32      45            |           5
%e A229950 33      49        | | | |
%e A229950 ...
%Y A229950 Partial sums of A229951.
%Y A229950 Cf. A000005, A139250, A229940, A229942, A229951.
%K A229950 nonn
%O A229950 0,6
%A A229950 _Omar E. Pol_, Oct 04 2013