A272532 - OEIS

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A272532

Single bit representation of the sum of two sinusoids with periods 2 and 2*sqrt(2).

1, 0, 1, 1, 0, 1, 1, 0, 1, 0, 0, 1, 0, 0, 1, 0, 1, 1, 0, 1, 1, 0, 1, 1, 0, 1, 0, 0, 1, 0, 0, 1, 0, 1, 1, 0, 1, 1, 0, 1, 1, 0, 1, 0, 0, 1, 0, 0, 1, 0, 1, 1, 0, 1, 1, 0, 1, 0, 0, 1, 0, 0, 1, 0, 0, 1, 0, 1, 1, 0, 1, 1, 0, 1, 0, 0, 1, 0, 0, 1, 0, 0, 1, 0, 1, 1, 0, 1, 1, 0, 1, 0, 0, 1, 0, 0, 1, 0, 1, 1, 0, 1, 1, 0, 1, 1, 0, 1, 0, 0, 1, 0, 0, 1, 0, 1, 1, 0, 1, 1

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OFFSET

1,1

COMMENTS

Since the ratio of the two periods is irrational, the sequence is strictly non-periodic.

From the factorized expression of the corresponding real function of x : 2*cos(2Pi((2 - sqrt(2))/8)x)*sin(2Pi((2 + sqrt(2))/8)x), it is possible to see that the largest distance between consecutive zeros is not greater than the shortest semi-period, 4/(2 + sqrt(2)), that is smaller than 2, and from this it follows that there are no more than two consecutive 0's or 1's.

LINKS

Table of n, a(n) for n=1..120.

Andres Cicuttin, Several segments at different scales of the fractal walk starting at (0,0) with step of unit length turning right if a(n)=1 and left if a(n)=0, except when this rule determines a decrement in the horizontal axes which in that case the step is equal to previous one

FORMULA

a(n) = floor( (1 + sin(2*Pi*(1/2)*n) + sin(2*Pi*(1/(2*Sqrt[2]))*n)) mod 2).

MATHEMATICA

nmax=120 ; Table[If[Sin[2*Pi*(1/2)*n]+Sin[2*Pi*(1/(2*Sqrt[2]))*n]<0, 0, 1], {n, 1, nmax}]

CROSSREFS

Conjectured quasiperiodicity in A271591 and A272170. A083035.

Sequence in context: A319843 A309847 A266786 * A166946 A144612 A174208

Adjacent sequences: A272529 A272530 A272531 * A272533 A272534 A272535

KEYWORD

nonn,base

AUTHOR

Andres Cicuttin, May 02 2016

STATUS

approved