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A239797
Decimal expansion of square root of 3 divided by cube root of 4.
2
1, 0, 9, 1, 1, 2, 3, 6, 3, 5, 9, 7, 1, 7, 2, 1, 4, 0, 3, 5, 6, 0, 0, 7, 2, 6, 1, 4, 1, 8, 9, 8, 0, 8, 8, 8, 1, 3, 2, 5, 8, 7, 3, 3, 3, 8, 7, 4, 0, 3, 0, 0, 9, 4, 0, 7, 0, 3, 6, 4, 1, 0, 7, 3, 2, 3, 6, 7, 8, 0, 1, 1, 0, 0, 5, 7, 2, 2, 3, 7, 4, 2, 0, 3, 3, 3, 3, 0, 0, 8, 3, 8, 2, 1, 7, 7
OFFSET
1,3
COMMENTS
This is the principal square root of 3 divided by the principal cube root of 4. This number is the imaginary part of a complex cubic root of 2, namely -2^(1/3)/2 + sqrt(-3)/4^(1/3). (The other complex cubic root of 2 is the same except for the sign of the imaginary part.)
An algebraic number of degree 6. - Charles R Greathouse IV, Apr 14 2014
FORMULA
2^(1/3)/2 = 1/2^(2/3) = 1/4^(1/3).
(-2^(1/3)/2 + sqrt(-3)/4^(1/3))^3 = 2.
Equals Product_{n >= 1} 1/(1 - 1/(6*n - 2)^2 ). - Fred Daniel Kline, Dec 19 2015
EXAMPLE
1.0911236359717214...
MATHEMATICA
RealDigits[Sqrt[3]/4^(1/3), 10, 100][[1]]
PROG
(PARI) polrootsreal(16*x^6-27)[2] \\ Charles R Greathouse IV, Apr 14 2014
CROSSREFS
Cf. A235362.
Sequence in context: A322107 A180839 A272232 * A010163 A200128 A225537
KEYWORD
cons,nonn
AUTHOR
Alonso del Arte, Mar 27 2014
STATUS
approved