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 A229950 Total number of toothpicks after n-th stage in a toothpick structure in which the toothpicks represent the 1's of triangle A229940. 6
 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, 36, 37, 40, 41, 44, 45, 49, 52, 56, 57, 61, 64, 68, 69, 73, 75, 79, 81, 85, 88, 92, 92, 96, 99, 104, 107, 112, 115, 120, 122, 127, 131, 136, 137, 142, 146, 151, 153 (list; graph; refs; listen; history; text; internal format)
 OFFSET 0,6 COMMENTS 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=1. See example and Link section. LINKS Omar E. Pol, Illustration of initial terms of the divisor function (A000005), see the third picture. N. J. A. Sloane, Catalog of Toothpick and Cellular Automata Sequences in the OEIS EXAMPLE Illustration of initial terms: --------------------------------------- n      a(n)       Diagram      A000005 --------------------------------------- 0       0 1       0 2       0                         1 3       1         | 4       1                         2 5       2         | 6       2                         2 7       3         | 8       3                         3 9       5         | | 10      6           |             2 11      8         | | 12      8                         4 13      10        | | 14      11          |             2 15      13        | | 16      13                        4 17      15        | | 18      16          |             3 19      19        | | | 20      20            |           4 21      23        | | | 22      25          | |           2 23      28        | | | 24      28                        6 25      31        | | | 26      33          | |           2 27      36        | | | 28      37            |           4 29      40        | | | 30      41          |             4 31      44        | | | 32      45            |           5 33      49        | | | | ... CROSSREFS Partial sums of A229951. Cf. A000005, A139250, A229940, A229942, A229951. Sequence in context: A062303 A180682 A227426 * A050318 A130841 A002095 Adjacent sequences:  A229947 A229948 A229949 * A229951 A229952 A229953 KEYWORD nonn AUTHOR Omar E. Pol, Oct 04 2013 STATUS approved

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Last modified February 22 23:44 EST 2020. Contains 332157 sequences. (Running on oeis4.)