%I #6 Jul 10 2017 22:50:50
%S 2,4,7,10,14,19,26,35,45,57,71,87,106,127,151,178,208,242,279,320,366,
%T 417,473,534,601,676,759,849,947,1054,1172,1302,1442,1594,1759,1939,
%U 2136,2346,2573,2819,3086,3376,3685,4018,4379,4770,5192,5642,6126,6650
%N Length of n-th iterate of the mapping 00->1000, 10->011, starting with 00.
%t z = 100; (* number of iterations *)
%t s = {0, 0}; w[0] = StringJoin[Map[ToString, s]];
%t w[n_] := StringReplace[w[n - 1], {"00" -> "1000", "10" -> "011"}]
%t Table[StringLength[w[n]], {n, 0, z}]
%Y Cf. A288226.
%K nonn,easy
%O 0,1
%A _Clark Kimberling_, Jul 10 2017