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A229951
Number of toothpicks added at n-th stage to the toothpick structure of A229950.
5
0, 0, 0, 1, 0, 1, 0, 1, 0, 2, 1, 2, 0, 2, 1, 2, 0, 2, 1, 3, 1, 3, 2, 3, 0, 3, 2, 3, 1, 3, 1, 3, 1, 4, 3, 4, 1, 4, 3, 4, 1, 4, 2, 4, 2, 4, 3, 4, 0, 4, 3, 5, 3, 5, 3, 5, 2, 5, 4, 5, 1, 5, 4, 5, 2, 5, 3, 5, 3, 5, 3, 5, 1, 6, 5, 6, 4, 6, 4, 6, 2, 6, 5, 6, 2, 6, 5
OFFSET
0,10
COMMENTS
Essentially the first differences of A229950.
Also [0, 0, 0] together the row sums of triangle A229940.
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.
EXAMPLE
Illustration of initial terms:
----------------------------------------
n a(n) Diagram A000005
----------------------------------------
0 0
1 0
2 0 1
3 1 |
4 0 2
5 1 |
6 0 2
7 1 |
8 0 3
9 2 | |
10 1 | 2
11 2 | |
12 0 4
13 2 | |
14 1 | 2
15 2 | |
16 0 4
17 2 | |
18 1 | 3
19 3 | | |
20 1 | 4
21 3 | | |
22 2 | | 2
23 3 | | |
24 0 6
25 3 | | |
26 2 | | 2
27 3 | | |
28 1 | 4
29 3 | | |
30 1 | 4
31 3 | | |
32 1 | 5
33 4 | | | |
...
CROSSREFS
KEYWORD
nonn,tabf
AUTHOR
Omar E. Pol, Oct 04 2013
STATUS
approved