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%I #19 Jun 10 2020 08:17:53
%S 1,1,1,2,1,9,14,16,7,25,110,18,351,91,295,32,578,81,285,240,630,462,
%T 1058,552,300,351,567,2156,1044,1770,2759,2368,1100,969,3920,1584
%N Maximum period of cellular automaton rule 110 in a cyclic universe of width n.
%C a(n) >= A180001(n), and this sequence agrees with A180001 up to n=11.
%H Eric Weisstein's World of Mathematics, <a href="http://mathworld.wolfram.com/Rule110.html">Rule 110</a>
%H <a href="http://oeis.org/index/Ce#cell">Index entries for sequences related to cellular automata</a>
%e The 12 cell pattern
%e 000100110111
%e 001101111101
%e 011111000111
%e 110001001101
%e 010011011111
%e 110111110001
%e 011100010011
%e 110100110111
%e 011101111100
%e 110111000100
%e 111101001101
%e 000111011111
%e 001101110001
%e 011111010011
%e 110001110111
%e 010011011100
%e 110111110100
%e 111100011101
%e 000100110111
%e Has period 18, which is the maximum possible, so a(12)=18
%t f[list_] := -Subtract @@ Flatten[Map[Position[#, #[[-1]]] &, NestWhileList[CellularAutomaton[110], list, Unequal, All], {0}]]; ma[n_] := Max[Table[f[IntegerDigits[i, 2, n]], {i, 0, 2^n - 1}]]; Table[ma[n], {n, 1, 10}]
%Y Cf. A180001, A161903, A006978, A332717, A332718.
%K nonn,hard,more
%O 1,4
%A _Ben Branman_, Jan 14 2012
%E a(19)-a(36) from _Lars Blomberg_, Dec 24 2015
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