OFFSET
1
COMMENTS
Conjecture: The number of letters (0's and 1's) in the n-th iterate of the mapping is given by A192967(n+2) for n >= 0.
Iterates, starting with 00:
00
1000
100111000
10011011100111000
1001101100111110011011100111000
100110110011110011011111001101100111110011011100111000
No iterate is an initial subword of its successor.
LINKS
Clark Kimberling, Table of n, a(n) for n = 1..10000
MATHEMATICA
s = {0, 0}; w[0] = StringJoin[Map[ToString, s]];
w[n_] := StringReplace[w[n - 1], {"00" -> "1000", "10" -> "10011"}]
Table[w[n], {n, 0, 8}]
st = ToCharacterCode[w[11]] - 48 (* A288929 *)
Flatten[Position[st, 0]] (* A288930 *)
Flatten[Position[st, 1]] (* A288931 *)
Table[StringLength[w[n]], {n, 1, 35}] (* A192967 conjectured *)
CROSSREFS
KEYWORD
nonn,easy
AUTHOR
Clark Kimberling, Jun 25 2017
EXTENSIONS
Definition corrected by Georg Fischer, May 28 2021
STATUS
approved