OFFSET
0,2
COMMENTS
Generation n (starting from the generation 0: 1) cut after the central 1-column and interpreted as a binary number.
Decimal representation of the x-axis, from the left edge to the origin, of the n-th stage of growth of the two-dimensional cellular automaton defined by "Rule 518", based on the 5-celled von Neumann neighborhood. Initialized with a single black (ON) cell at stage zero. - Robert Price, Feb 22 2017
LINKS
N. J. A. Sloane, On the Number of ON Cells in Cellular Automata, arXiv:1503.01168 [math.CO], 2015
Eric Weisstein's World of Mathematics, Elementary Cellular Automaton
S. Wolfram, A New Kind of Science
Wolfram Research, Wolfram Atlas of Simple Programs
MAPLE
bit_n := (x, n) -> `mod`(floor(x/(2^n)), 2);
sigmacut := proc(n): if (0 = n) then (1)
else sum('((bit_n(sigmagen(n-1), i+1+n-1)+bit_n(sigmagen(n-1), i+n-1)+bit_n(sigmagen(n-1), i-1+n-1)) mod 2)*(2^i)', 'i'=0..(n)) fi: end:
CROSSREFS
KEYWORD
nonn
AUTHOR
Antti Karttunen, Feb 09 1999
STATUS
approved