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 A173461 Number of cells turned "ON" at n-th stage of cellular automaton of A173460. 4
 0, 1, 8, 12, 8, 52, 12, 12, 84, 36, 28, 188, 12, 12, 84, 36, 36, 252, 36, 36, 252, 108, 92, 628, 12, 12, 84, 36, 36, 252, 36, 36, 252, 108, 108, 756, 36, 36, 252, 108, 108, 756, 108, 108, 756, 324, 292, 2012, 12, 12, 84, 36, 36, 252, 36, 36, 252, 108, 108 (list; graph; refs; listen; history; text; internal format)
 OFFSET 0,3 COMMENTS Essentially the first differences of A173460. It appears that row lengths give the absolute values of A110164. - Omar E. Pol, Apr 25 2013 LINKS Table of n, a(n) for n=0..58. 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, for n>=3 let i=n/3+1, j=A147610(i), if 2^r==i for some r then let c1=2^(r+1), c2=2^(r+4) else let c1=c2=0, finally when (n MOD 3)=0,1,2 let a(n)=12*j, 12*j-c1, 84*j-c2. (Found empirically) [Lars Blomberg, Apr 23 2013] EXAMPLE From Omar E. Pol, Apr 25 2013: (Start) When written as an irregular triangle begins: 0; 1,8; 12,8,52; 12,12,84,36,28,188; 12,12,84,36,36,252,36,36,252,108,92,628; 12,12,84,36,36,252,36,36,252,108,108,756,36,36,252,108,108,756,108,108,756,324,292,2012; 12,12,84,36,36,252,36,36,252,108,108,... (End) CROSSREFS Cf. A139250, A139251, A173457, A173460, A173462, A173463. Sequence in context: A152077 A215696 A325809 * A335160 A295782 A331801 Adjacent sequences: A173458 A173459 A173460 * A173462 A173463 A173464 KEYWORD nonn,tabf AUTHOR Omar E. Pol, Feb 18 2010 EXTENSIONS More terms a(14)-a(17) from Omar E. Pol, Sep 25 2011 a(18)-a(58) from Lars Blomberg, Apr 23 2013 STATUS approved

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Last modified April 20 12:36 EDT 2024. Contains 371844 sequences. (Running on oeis4.)