A151922 Number of first-quadrant cells (including the two boundaries) that are "ON" after n-th stage of the Holladay-Ulam cellular automaton.
1, 3, 5, 9, 11, 15, 19, 29, 31, 35, 39, 49, 53, 63, 73, 101, 103, 107, 111, 121, 125, 135, 145, 173, 177, 187, 197, 225, 235, 263, 291, 373, 375, 379, 383, 393, 397, 407, 417, 445, 449, 459, 469, 497, 507, 535, 563, 645
Offset: 0
Links
- Paolo Xausa, Table of n, a(n) for n = 0..10000
- 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
- Index entries for sequences related to cellular automata
Programs
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Mathematica
A151922list[nmax_]:=Accumulate[Join[{1},3^(DigitCount[Range[nmax],2,1]-1)+1]];A151922list[100] (* Paolo Xausa, Jun 29 2023 *)
Formula
a(n) = A079316(2n).
Extensions
Extended (a(30)-a(47)) and edited by Omar E. Pol, Nov 21 2010
Comments