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
LINKS
G. C. Greubel, Table of n, a(n) for n = 1..10000
William Stein, Algebraic Number Theory, a Computational Approach, p. 69 (in the PDF), Example 6.1.1, or Discriminants and Norms chapter (HTML).
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
KEYWORD
cons,nonn
AUTHOR
Alonso del Arte, Mar 27 2014
STATUS
approved