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 A170891 First differences of the toothpick sequence A170890. 4
 0, 1, 1, 2, 3, 3, 4, 7, 8, 8, 6, 10, 8, 10, 12, 20, 20, 16, 12, 14, 8, 10, 12, 20, 20, 18, 18, 24, 22, 28, 40, 56, 52, 38, 28, 22, 8, 10, 12, 20, 20, 18, 18, 24, 22, 28, 40, 56, 52, 40, 34, 32, 22, 28, 40, 56, 54, 50, 56, 66, 68, 92, 132, 160, 138, 98, 68, 38 (list; graph; refs; listen; history; text; internal format)
 OFFSET 0,4 COMMENTS Number of toothpicks added at n-th stage to the toothpick structure of A170890. - Omar E. Pol, Jan 31 2013 LINKS 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 EXAMPLE From Omar E. Pol, Jan 31 2013 (Start): If written as an irregular triangle in which rows 0..4 have length 1, it appears that row j has length 2^(j-5), if j >= 5. 0; 1; 1; 2; 3; 3; 4,7; 8,8,6,10; 8,10,12,20,20,16,12,14; 8,10,12,20,20,18,18,24,22,28,40,56,52,38,28,22; 8,10,12,20,20,18,18,24,22,28,40,56,52,40,34,32,22,28,40,56,54,50,56,66,68,92,132,160,138,98,68,38; (End) CROSSREFS Cf. A139250, A139251, A170890, A170885, A170887, A170889, A170893. Sequence in context: A035540 A114863 A152980 * A035535 A154309 A249579 Adjacent sequences:  A170888 A170889 A170890 * A170892 A170893 A170894 KEYWORD nonn,tabf AUTHOR Omar E. Pol, Jan 09 2010 EXTENSIONS a(9) corrected by Omar E. Pol, following an observation by Kevin Ryde, Jan 29 2013 Terms beyond a(9) from M. F. Hasler, Jan 29 2013 STATUS approved

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Last modified December 14 21:22 EST 2018. Contains 318138 sequences. (Running on oeis4.)