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A348909 Decimal expansion of the real root of x^3 + x^2 - 2*x - 4. 2
1, 6, 5, 8, 9, 6, 7, 0, 8, 1, 9, 1, 6, 9, 9, 4, 0, 7, 9, 3, 4, 6, 7, 7, 5, 1, 5, 6, 7, 8, 4, 0, 1, 5, 6, 1, 5, 2, 4, 3, 9, 9, 3, 3, 4, 4, 5, 6, 2, 7, 7, 7, 1, 0, 0, 3, 5, 2, 2, 1, 5, 4, 8, 8, 9, 8, 4, 1, 6, 8, 0, 2, 0, 7, 8, 0, 3, 3, 6, 0, 7, 4, 8, 4, 4, 2, 9, 0, 7, 8 (list; constant; graph; refs; listen; history; text; internal format)
OFFSET
1,2
COMMENTS
This constant appears in the upper bounds formula of both the peak sidelobe level and the peak cross-correlation of Rudin-Shapiro sequences.
LINKS
Daniel J. Katz and Courtney M. van der Linden, Peak Sidelobe Level and Peak Crosscorrelation of Golay-Rudin-Shapiro Sequences, arXiv:2108.07318 [cs.IT], 2021. See Theorems 1.3, 1.4 and 1.5, pp. 4-5.
FORMULA
Equals ((44 + 3*sqrt(177))^(1/3) + (44 - 3*sqrt(177))^(1/3) - 1)/3.
EXAMPLE
1.6589670819169940793467751567840...
MATHEMATICA
First[RealDigits[N[Root[x^3+x^2-2x-4, x, 1], 90]]]
PROG
(PARI) solve(x=0, 2, x^3 + x^2 - 2*x - 4) \\ Michel Marcus, Nov 03 2021
CROSSREFS
Sequence in context: A335165 A080799 A262512 * A272696 A048236 A193719
KEYWORD
nonn,cons
AUTHOR
Stefano Spezia, Nov 03 2021
STATUS
approved

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Last modified April 23 22:36 EDT 2024. Contains 371917 sequences. (Running on oeis4.)