%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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