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A288508
0-limiting word of the mapping 00->0101, 10->001, starting with 00.
4
0, 0, 0, 1, 0, 0, 1, 0, 1, 0, 1, 0, 0, 1, 0, 1, 0, 1, 0, 0, 1, 0, 0, 0, 1, 0, 0, 0, 1, 0, 1, 0, 1, 0, 0, 1, 0, 0, 0, 1, 0, 0, 0, 1, 0, 1, 0, 1, 0, 0, 1, 0, 0, 1, 0, 0, 1, 0, 0, 0, 1, 0, 0, 1, 0, 0, 1, 0, 0, 0, 1, 0, 0, 0, 1, 0, 0, 0, 1, 0, 1, 0, 1, 0, 0, 1
OFFSET
1
COMMENTS
Iterates, starting with 00:
00
0101
00011
0101011
000100111
010100010111
00010010101001111
01010001000100100101111
000100101010010101001000100011111
The 0-limiting word is the limit taken over even-numbered iterations of the mapping.
Conjecture: the number of letters (0's and 1's) in the n-th iterate is given by A288511(n).
LINKS
EXAMPLE
The first 5 even-numberd iterates:
00
00011
000100111
00010010101001111
000100101010010101001000100011111
MATHEMATICA
s = {0, 0}; w[0] = StringJoin[Map[ToString, s]];
w[n_] := StringReplace[w[n - 1], {"00" -> "0101", "10" -> "001"}]
Table[w[n], {n, 0, 8}]
st = ToCharacterCode[w[18]] - 48 (* A288508 *)
Flatten[Position[st, 0]] (* A288509 *)
Flatten[Position[st, 1]] (* A288510 *)
Table[StringLength[w[n]], {n, 1, 35}] (* A288511 conjectured *)
CROSSREFS
KEYWORD
nonn,easy
AUTHOR
Clark Kimberling, Jun 12 2017
STATUS
approved