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 A173457 Number of cell turned "ON" at n-th stage of cellular automaton of A173456. 5
 0, 1, 8, 12, 4, 28, 36, 4, 28, 36, 12, 84, 108, 4, 28, 36, 12, 84, 108, 12, 84, 108, 36, 252, 324, 4, 28, 36, 12, 84, 108, 12, 84, 108, 36, 252, 324, 12, 84, 108, 36, 252, 324, 36, 252, 324, 108, 756, 972, 4, 28, 36, 12, 84, 108, 12, 84, 108, 36, 252, 324 (list; graph; refs; listen; history; text; internal format)
 OFFSET 0,3 COMMENTS Essentially the first differences of A173456. It appears that row lengths give A098011. After the initial zero, it appears that row lengths give the absolute values of A110164. - Omar E. Pol, Apr 22 2013 LINKS Lars Blomberg, Table of n, a(n) for n = 0..6000 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 FORMULA a(0)=0, a(1)=1, a(2)=8, a(3)=12, for n>=4 when (n MOD 3)=0,1,2 let m=36,4,28 then a(n)=m*A147610((n + 2) / 3). (Found empirically) [Lars Blomberg, Apr 22 2013] EXAMPLE From Omar E. Pol, Apr 22 2013 (Start): When written as an irregular triangle begins: 0; 1; 8,12; 4,28,36; 4,28,36,12,84,108; 4,28,36,12,84,108,12,84,108,36,252,324; 4,28,36,12,84,108,12,84,108,36,252,324,12,84,108,36,252,324,36,252,324,108,756,972; 4,28,36,12,84,108,12,84,108,36,252,324,... (End) CROSSREFS Cf. A139250, A139251, A173456, A173458, A173459, A173461. Sequence in context: A070697 A004473 A114404 * A033198 A072900 A203836 Adjacent sequences:  A173454 A173455 A173456 * A173458 A173459 A173460 KEYWORD nonn,tabf AUTHOR Omar E. Pol, Feb 18 2010 EXTENSIONS a(41)-a(60) from Lars Blomberg, Apr 22 2013 STATUS approved

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Last modified January 27 21:15 EST 2022. Contains 350653 sequences. (Running on oeis4.)