OFFSET
1,5
LINKS
Clark Kimberling, Table of n, a(n) for n = 1..10000
EXAMPLE
As a word, A003849 = 01001010010010100..., and replacing each 1010 by 2 gives 01002010020201002010020201002020100201...
MATHEMATICA
s = Nest[Flatten[# /. {0 -> {0, 1}, 1 -> {0}}] &, {0}, 13] ; (* A003849 *)
w = StringJoin[Map[ToString, s]]
w1 = StringReplace[w, {"1010" -> "2"}]
st = ToCharacterCode[w1] - 48; (* A285680 *)
Flatten[Position[st, 0]]; (* A285681 *)
Flatten[Position[st, 1]]; (* A285682 *)
Flatten[Position[st, 2]]; (* A285683 *)
CROSSREFS
KEYWORD
nonn,easy
AUTHOR
Clark Kimberling, May 11 2017
STATUS
approved