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A285431
Fixed point of the morphism 0->11, 1-> 110.
5
1, 1, 0, 1, 1, 0, 1, 1, 1, 1, 0, 1, 1, 0, 1, 1, 1, 1, 0, 1, 1, 0, 1, 1, 0, 1, 1, 0, 1, 1, 1, 1, 0, 1, 1, 0, 1, 1, 1, 1, 0, 1, 1, 0, 1, 1, 0, 1, 1, 0, 1, 1, 1, 1, 0, 1, 1, 0, 1, 1, 1, 1, 0, 1, 1, 0, 1, 1, 1, 1, 0, 1, 1, 0, 1, 1, 1, 1, 0, 1, 1, 0, 1, 1, 0, 1
OFFSET
1
LINKS
EXAMPLE
0 -> 11 -> 110110- -> 1101101111011011 -> 11011011110110111101101101101111011011110110 ->
MATHEMATICA
s = Nest[Flatten[# /. {0 -> {1, 1}, 1 -> {1, 1, 0}}] &, {0}, 13] (* A285431 *)
Flatten[Position[s, 0]] (* A026368 *)
Flatten[Position[s, 1]] (* A026367 *)
PROG
(Python)
from itertools import islice
def A285431_gen(): # generator of terms
a, l = [1, 1], 0
while True:
yield from a[l:]
c = sum(([1, 1, 0] if d else [1, 1] for d in a), start=[])
l, a = len(a), c
A285431_list = list(islice(A285431_gen(), 30)) # Chai Wah Wu, Nov 30 2023
CROSSREFS
Sequence in context: A080764 A291137 A285421 * A267621 A374039 A014114
KEYWORD
nonn,easy
AUTHOR
Clark Kimberling, Apr 29 2017
STATUS
approved