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%I #10 Jan 05 2013 02:29:58
%S 0,1,2,4,4,4,4,7,8,4,4,8,12,8,8,13,16,4,4,8,12,16,16,20,24,12,8,16,28,
%T 16,16,25,32,4,4,8,12,16,16,22,32,26,20,24,40,32,40,41,48,20,8
%N Number of toothpicks or D-toothpicks added at n-th stage in the structure of the D-toothpick "narrow" triangle of A220522.
%C Essentially the first differences of A220522. First differs from A194443 at a(47).
%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 begins:
%e 0;
%e 1;
%e 2;
%e 4,4;
%e 4,4,7,8;
%e 4,4,8,12,8,8,13,16;
%e 4,4,8,12,16,16,20,24,12,8,16,28,16,16,25,32;
%e 4,4,8,12,16,16,22,32,26,20,24,40,32,40,41,48,20,8,...
%Y Cf. A139250, A139251, A194441, A194443, A194445, A220521, A220522.
%K nonn,more
%O 0,3
%A _Omar E. Pol_, Dec 15 2012