login
A267139
Decimal representation of the n-th iteration of the "Rule 103" elementary cellular automaton starting with a single ON (black) cell.
2
1, 6, 6, 117, 60, 1931, 376, 32535, 752, 523823, 1504, 8387679, 3008, 134215871, 6016, 2147479935, 12032, 34359730943, 24064, 549755799039, 48128, 8796092992511, 96256, 140737488295935, 192512, 2251799813566463, 385024, 36028797018726399, 770048
OFFSET
0,2
FORMULA
Conjectures from Colin Barker, Jan 11 2016 and Apr 19 2019: (Start)
a(n) = 19*a(n-2) - 50*a(n-4) + 32*a(n-6) for n > 10.
G.f.: (1 + 6*x - 13*x^2 + 3*x^3 - 4*x^4 + 8*x^5 - 496*x^6 + 1504*x^7 - 3584*x^8 - 1536*x^9 + 4096*x^10) / ((1-x)*(1+x)*(1-4*x)*(1+4*x)*(1-2*x^2)). (End)
MATHEMATICA
rule=103; 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: A320824 A085804 A012125 * A170915 A328186 A123190
KEYWORD
nonn,easy
AUTHOR
Robert Price, Jan 10 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