login

Year-end appeal: Please make a donation to the OEIS Foundation to support ongoing development and maintenance of the OEIS. We are now in our 61st year, we have over 378,000 sequences, and we’ve reached 11,000 citations (which often say “discovered thanks to the OEIS”).

A267003
Decimal representation of the n-th iteration of the "Rule 83" elementary cellular automaton starting with a single ON (black) cell.
2
1, 5, 8, 111, 64, 1919, 512, 31743, 4096, 516095, 32768, 8323071, 262144, 133693439, 2097152, 2143289343, 16777216, 34326183935, 134217728, 549487378431, 1073741824, 8793945538559, 8589934592, 140720308486143, 68719476736, 2251662374731775, 549755813888
OFFSET
0,2
FORMULA
Conjectures from Colin Barker, Jan 08 2016 and Apr 19 2019: (Start)
a(n) = 25*a(n-2)-152*a(n-4)+128*a(n-6) for n>5.
G.f.: (1+2*x)*(1+3*x-23*x^2+32*x^3-48*x^4) / ((1-x)*(1+x)*(1-4*x)*(1+4*x)*(1-8*x^2)).
(End)
MATHEMATICA
rule=83; 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]], 2], {k, 1, rows}] (* Decimal Representation of Rows *)
CROSSREFS
Sequence in context: A025518 A361225 A356826 * A151827 A258044 A162571
KEYWORD
nonn,easy
AUTHOR
Robert Price, Jan 08 2016
EXTENSIONS
Removed an unjustified claim that Colin Barker's conjectures are correct. Removed a program based on a conjecture. - Michael De Vlieger, Jun 13 2022
STATUS
approved