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First differences of toothpick sequence A170888.
4

%I #11 Feb 24 2021 02:48:19

%S 0,1,2,4,4,4,6,10,8,4,6,10,10,12,20,26,16,4,6,10,10,12,20,26,18,12,20,

%T 28,30,42,64,66,32,4,6,10,10,12,20,26,18,12,20,28,30,42,64,66,34,12,

%U 20,28,30,42,64,68,46,42,66,84,100,146,192,162,64,4,6,10,10,12,20,26,18,12

%N First differences of toothpick sequence A170888.

%H David Applegate, Omar E. Pol and N. J. A. Sloane, <a href="/A000695/a000695_1.pdf">The Toothpick Sequence and Other Sequences from Cellular Automata</a>, Congressus Numerantium, Vol. 206 (2010), 157-191. [There is a typo in Theorem 6: (13) should read u(n) = 4.3^(wt(n-1)-1) for n >= 2.]

%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>

%e From _Omar E. Pol_, Jan 30 2013 (Start):

%e Written as an irregular triangle:

%e 0;

%e 1;

%e 2;

%e 4,4;

%e 4,6,10,8;

%e 4,6,10,10,12,20,26,16;

%e 4,6,10,10,12,20,26,18,12,20,28,30,42,64,66,32;

%e 4,6,10,10,12,20,26,18,12,20,28,30,42,64,66,34,12,20,28,30,42,64,68,46,42,66,84,100,146,192,162,64;

%e (End)

%Y Cf. A139250, A139251, A160407, A170887, A170888, A170891, A170893.

%K nonn,tabf

%O 0,3

%A _Omar E. Pol_, Jan 09 2010

%E Terms beyond a(10) from _R. J. Mathar_, Jan 25 2010