OFFSET
0,2
REFERENCES
S. Wolfram, A New Kind of Science, Wolfram Media, 2002; p. 55.
LINKS
Robert Price, Table of n, a(n) for n = 0..1000
Eric Weisstein's World of Mathematics, Elementary Cellular Automaton
S. Wolfram, A New Kind of Science
FORMULA
Conjectures from Colin Barker, Jan 19 2016: (Start)
a(n) = 110*a(n-1) - 999*a(n-2) - 110*a(n-3) + 1000*a(n-4) for n > 4.
G.f.: (1 - x^2 + 10*x^3 - 1000*x^4) / ((1-x)*(1+x)*(1-10*x)*(1-100*x)).
(End)
MATHEMATICA
rule=199; rows=20; ca=CellularAutomaton[rule, {{1}, 0}, rows-1, {All, All}]; (* Start with single black cell *) catri=Table[Take[ca[[k]], {rows-k+1, rows+k-1}], {k, 1, rows}]; (* truncated list of each row *) Table[FromDigits[catri[[k]]], {k, 1, rows}] (* binary representation of rows *)
CROSSREFS
KEYWORD
nonn
AUTHOR
Robert Price, Jan 19 2016
STATUS
approved