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 A187211 First differences of A187210. 11
 0, 1, 4, 7, 12, 22, 20, 22, 40, 54, 40, 22, 40, 54, 56, 70, 120, 134, 72, 22, 40, 54, 56, 70, 120, 134, 88, 70, 120, 150, 168, 246, 360, 326, 136, 22, 40, 54, 56, 70, 120, 134, 88, 70, 120, 150, 168, 246, 360, 326, 152, 70, 120, 150, 168, 246, 360, 342, 232, 246, 376, 454, 568, 838, 1032 (list; graph; refs; listen; history; text; internal format)
 OFFSET 0,3 COMMENTS Number of Q-toothpicks added at n-th stage to the Q-toothpick structure of A187210. For the connection with A139251, the first differences of the toothpick sequence A139250, see the Formula section. - Omar E. Pol, Apr 02 2016 LINKS Nathaniel Johnston, Table of n, a(n) for n = 0..177 David Applegate, The movie version 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.] Nathaniel Johnston, C script Nathaniel Johnston, The Q-Toothpick Cellular Automaton N. J. A. Sloane, Catalog of Toothpick and Cellular Automata Sequences in the OEIS FORMULA a(2^n + 2) = 16 + 8(2^(n-1) - 1), n >= 3. [Nathaniel Johnston, Mar 26 2011] From Omar E. Pol, Apr 02 2016: (Start) a(n) = floor(sqrt(2*n^3)), if 0<=n<=2 or n=6. a(n) = 2*A139251(n-2) + A267699(n-2) + A267695(n-1), if 3<=n<=5 or n>=7. (End) EXAMPLE Written as an irregular triangle the sequence begins: 0; 1; 4; 7; 12; 22, 20; 22, 40, 54, 40; 22, 40, 54, 56, 70, 120, 134, 72; 22, 40, 54, 56, 70, 120, 134, 88, 70, 120, 150, 168, 246, 360, 326, 136; ... The rows of this triangle tend to A188156. From Omar E. Pol, Apr 02 2016: (Start) For n = 5 we have that A139251(5-2) = 4, A267699(5-2) = 7 and A267695(5-1) = 7, so a(5) = 2*4 + 7 + 7 = 22. For n = 10 we have that A139251(10-2) = 8, A267699(10-2) = 20 and A267695(10-1) = 4, so a(10) = 2*8 + 20 + 4 = 40. (End) Starting from a(3) = 7 the row lengths of triangle are the terms of A011782. - Omar E. Pol, Apr 04 2016 CROSSREFS Cf. A011782, A139250, A139251, A172472, A182841, A187210, A187221, A267695, A267699. Sequence in context: A117949 A228879 A010901 * A023624 A123194 A208668 Adjacent sequences:  A187208 A187209 A187210 * A187212 A187213 A187214 KEYWORD nonn,tabf AUTHOR Omar E. Pol, Mar 07 2011 EXTENSIONS Terms after a(7) from Nathaniel Johnston, Mar 26 2011 STATUS approved

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Last modified October 15 17:24 EDT 2019. Contains 328037 sequences. (Running on oeis4.)