A161412 - OEIS

%I #10 Jun 14 2022 14:11:43

%S 0,1,2,3,5,9,12,15,19,25,29,34,39,49,58,63

%N V-toothpick sequence starting at the corner of an infinite square from which protrudes a half toothpick with an angle = Pi/6.

%C The sequence gives the number of V-toothpicks in the structure after n rounds. A161413 (the first differences) gives the number added at the n-th round.

%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>

%Y V-toothpick sequence: A161206.

%Y Cf. A139250, A160120, A160406, A161328, A161413.

%K more,nonn

%O 0,3

%A _Omar E. Pol_, Jun 10 2009