A357867 Numbers k such that A334499(k) is not divisible by k.
12, 15, 25, 28, 30, 39
Offset: 1
This is a front-end for the Online Encyclopedia of Integer Sequences, made by Christian Perfect. The idea is to provide OEIS entries in non-ancient HTML, and then to think about how they're presented visually. The source code is on GitHub.
For n=4, the evolution of a single cell is: 0001 0011 0111 <--= period starts 1101 0111 <--= again start of period etc, so a(4)=2.
a[n_] := -Subtract @@
Flatten[Map[Position[#, #[[-1]]] &,
NestWhileList[CellularAutomaton[110],
Prepend[Table[0, {n - 1}], 1], Unequal, All], {0}]]
def A180001(n): def bit(x,i): return (x >> i) & 1 rulemap = dict((tuple(bit(i,k) for k in reversed(range(3))), bit(110,i)) for i in range(8)) def neighbours(d, i): return tuple(d[k % n] for k in [i-1..i+1]) v = [0]*n; v[-1] = 1; history = [v] while True: v2 = [rulemap[neighbours(history[-1], i)] for i in range(n)] if v2 in history: return len(history)-history.index(v2) history.append(v2) # D. S. McNeil, Jan 15 2011
a[rule_, n_] := -Subtract @@ Flatten[Map[ Position[#, #[[-1]]] &,
NestWhileList[CellularAutomaton[rule],
Prepend[Table[0, {n - 1}], 1], Unequal, All], {0}]]
a[30, #] & /@ Range[10]
(* Bradley Klee, Apr 26 2020 *)
a[rule_, init_] := -Subtract @@ Flatten[Map[
Position[#, #[[-1]]] &, NestWhileList[CellularAutomaton[rule],
init, Unequal, All], {0}]]
tri[n_] := a[30, #] & /@ Tuples[{0, 1}, n];
tri /@ Range[7]
Max /@ %
(* Bradley Klee, Apr 26 2020 *)
For R = 45, the sequence {s(R,1)..s(R,10)} is 2,2,1,2,30,18,126,2,504,430 (see A334508), and s(45,10) = 430 is the greatest value of any s(R,10), so a(10) = 430/10 = 430.
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