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A188082
[nr+kr]-[nr]-[kr], where r=sqrt(3), k=1, [ ]=floor.
2
1, 1, 0, 1, 1, 1, 0, 1, 1, 1, 0, 1, 1, 0, 1, 1, 1, 0, 1, 1, 1, 0, 1, 1, 1, 0, 1, 1, 0, 1, 1, 1, 0, 1, 1, 1, 0, 1, 1, 1, 0, 1, 1, 0, 1, 1, 1, 0, 1, 1, 1, 0, 1, 1, 0, 1, 1, 1, 0, 1, 1, 1, 0, 1, 1, 1, 0, 1, 1, 0, 1, 1, 1, 0, 1, 1, 1, 0, 1, 1, 1, 0, 1, 1, 0, 1, 1, 1, 0, 1, 1, 1, 0, 1, 1, 1, 0, 1, 1, 0, 1, 1, 1, 0, 1, 1, 1, 0, 1, 1, 0, 1, 1, 1, 0, 1, 1, 1, 0, 1, 1, 1, 0, 1, 1, 0, 1, 1, 1, 0, 1, 1, 1, 0, 1, 1, 1, 0, 1, 1, 0, 1, 1, 1, 0, 1, 1, 1, 0, 1, 1, 1, 0
OFFSET
1
COMMENTS
The positions of 0 and 1 in this sequence are given by the Beatty sequences A003512 and A003511. See A187950.
This is A188068 shifted one place left.
The trajectory of 0 under the morphism 0 -> 110, 1 -> 1101. - N. J. A. Sloane, Sep 08 2016
LINKS
Jeffrey Shallit, Characteristic words as fixed points of homomorphisms, University of Waterloo Technical Report CS-91-72, 1991. See Example 2 with a=1, b=2.
Jeffrey Shallit, Characteristic words as fixed points of homomorphisms. See Example 2 with a=1, b=2. [Cached copy, with permission]
FORMULA
a(n)=[nr+r]-[nr]-[kr], where r=sqrt(3).
MATHEMATICA
r=3^(1/2); k=1;
seqA=Table[Floor[n*r+k*r]-Floor[n*r]-Floor[k*r],
{n, 1, 220}] (* A188082 *)
Flatten[Position[seqA, 0] ] (*A003512*)
Flatten[Position[seqA, 1] ] (*A003511*)
PROG
(Python)
from gmpy2 import isqrt
def A188082(n):
return int(isqrt(3*(n+1)**2) - isqrt(3*n**2)) - 1 # Chai Wah Wu, Oct 07 2016
CROSSREFS
Sequence in context: A230603 A229343 A085369 * A046980 A152822 A118831
KEYWORD
nonn
AUTHOR
Clark Kimberling, Mar 20 2011
STATUS
approved