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A112539
Half-baked Thue-Morse: at successive steps the sequence or its bit-inverted form is appended to itself.
3
1, 0, 1, 0, 0, 1, 0, 1, 1, 0, 1, 0, 0, 1, 0, 1, 0, 1, 0, 1, 1, 0, 1, 0, 0, 1, 0, 1, 1, 0, 1, 0, 1, 0, 1, 0, 0, 1, 0, 1, 1, 0, 1, 0, 0, 1, 0, 1, 0, 1, 0, 1, 1, 0, 1, 0, 0, 1, 0, 1, 1, 0, 1, 0, 0, 1, 0, 1, 1, 0, 1, 0, 0, 1, 0, 1, 1, 0, 1, 0, 1, 0, 1, 0, 0, 1, 0, 1, 1, 0, 1, 0, 0, 1, 0, 1, 0, 1, 0, 1, 1, 0, 1, 0, 0
OFFSET
1,1
EXAMPLE
Triangle begins:
1;
0;
1, 0;
0, 1, 0, 1;
1, 0, 1, 0, 0, 1, 0, 1;
0, 1, 0, 1, 1, 0, 1, 0, 0, 1, 0, 1, 1, 0, 1, 0;
1, 0, 1, 0, 0, 1, 0, 1, 1, 0, 1, 0, 0, 1, 0, 1, 0, 1, 0, 1, 1, 0, 1, 0, 0, 1, 0, 1, 1, 0, 1, 0;
...
MATHEMATICA
s = {1}; Do[s = Join[s, Mod[s + 1, 2]]; s = Join[s, s], {n, 4}]; s (* Robert G. Wilson v, Dec 22 2005 *)
PROG
(Python)
s = [1]
for _ in range(4):
s = s + [(x + 1) % 2 for x in s]
s = s + s
print(s) # Robert C. Lyons, Jan 19 2025
(PARI)
aiter(x) = my(s=[1]); for(i=1, x, s=concat(s, if(i%2, [1-e|e<-s], s))); s \\ Ruud H.G. van Tol, Jan 20 2025
CROSSREFS
Cf. A112865 (as +-1), A341389 (complement).
Sequence in context: A320167 A030658 A187950 * A104104 A188467 A039983
KEYWORD
easy,nonn
AUTHOR
Alexandre Losev, Dec 15 2005
EXTENSIONS
More terms from Robert G. Wilson v, Dec 22 2005
STATUS
approved