A160714 - OEIS

%I #6 Feb 24 2021 02:48:18

%S 0,1,2,5,6,9,12,21,22,25,28,37,40,49,58,85,112,113

%N T-toothpick sequence starting at the corner of an infinite square, but with angle = Pi/4.

%C The sequence gives the number of T-toothpicks after n rounds.

%C See A160172 for more information about T-toothpick sequences.

%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 Cf. A139250, A160172, A160173.

%K more,nonn

%O 0,3

%A _Omar E. Pol_, Jun 02 2009