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Number of toothpicks added to the spiral at the n-th stage.
Table of n, a(n) for n=1..73.
David Applegate, Omar E. Pol and N. J. A. Sloane, The Toothpick Sequence and Other Sequences from Cellular Automata, 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.]
N. J. A. Sloane, Catalog of Toothpick and Cellular Automata Sequences in the OEIS
Cf. A000045, A139250, A139251, A160426, A160427, A160800.
Sequence in context: A302828 A321622 A087266 * A177002 A079046 A079045
Adjacent sequences: A160798 A160799 A160800 * A160802 A160803 A160804
Omar E. Pol, May 26 2009
Terms after a(32) from Nathaniel Johnston, Mar 30 2011