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A242647 Sign of (the n-th continued fraction convergent to 2*Pi divided by the n-th convergent to Pi minus 2). 2
0, 1, -1, 1, -1, 1, -1, 0, 1, 0, 0, 0, 0, -1, 1, -1, 1, -1, 1, -1, 1, -1, 1, -1, 1, -1, 1, -1, 1, -1, 1, -1, 1, -1, 1, -1, 1, -1, 0, 0, 1, 0, -1, 1, -1, 1, -1, 1, -1, 1, -1, 1, 0, 0, 0, -1, 1, -1, 1, -1 (list; graph; refs; listen; history; text; internal format)
OFFSET

1

COMMENTS

Zeros appear in clusters (see A242857). Conjecture: Remove all zeros and the remaining terms will alternate signs.

REFERENCES

Hans Havermann, Posting to Math Fun Mailing List, May 22 2014.

LINKS

Hans Havermann, Table of n, a(n) for n = 1..10000

MATHEMATICA

Sign[Convergents[2*Pi, 200]/Convergents[Pi, 200]-2]

CROSSREFS

Cf. A242857; Convergents to 2*Pi: A046955 (assuming offset 0)/A242859; Convergents to Pi: A002485/A002486 (both assuming offset -1).

Sequence in context: A182067 A196147 A097325 * A167393 A275606 A106549

Adjacent sequences:  A242644 A242645 A242646 * A242648 A242649 A242650

KEYWORD

sign

AUTHOR

N. J. A. Sloane, May 23 2014

STATUS

approved

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Last modified January 17 14:12 EST 2019. Contains 319225 sequences. (Running on oeis4.)