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 A220521 Number of toothpicks or D-toothpicks added at n-th stage in the toothpick structure of A220520. 12

%I

%S 0,1,2,4,4,4,4,8,8,4,4,8,12,16,12,16,16,4,4,8,12,16,20,24,26,24,12,20,

%T 32,40,28,32,32,4,4,8,12,16,20,24,26,24,20,32,44,64,52,48,54,40,12,20,

%U 36,48,56,64,74,76,30,44,72,88,60,64,64,4,4,8,12

%N Number of toothpicks or D-toothpicks added at n-th stage in the toothpick structure of A220520.

%C Essentially the first differences of A220520. First differs from A194441 at a(14).

%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 Written as an irregular triangle:

%e 0;

%e 1;

%e 2;

%e 4,4;

%e 4,4,8,8;

%e 4,4,8,12,16,12,16,16;

%e 4,4,8,12,16,20,24,26,24,12,20,32,40,28,32,32;

%e 4,4,8,12,16,20,24,26,24,20,32,44,64,52,48,54,40,12,20,...

%Y Cf. A139250, A139251, A194441, A194443.

%K nonn,less

%O 0,3

%A _Omar E. Pol_, Dec 15 2012

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Last modified December 6 21:48 EST 2019. Contains 329809 sequences. (Running on oeis4.)