- Gauss's constant
In
mathematics , Gauss's constant, denoted by "G", is defined as thereciprocal of thearithmetic-geometric mean of 1 and thesquare root of 2 :: G = frac{1}{mathrm{agm}(1, sqrt{2})} = 0.8346268dots
The constant is named after
Carl Friedrich Gauss , who on May 30, 1799 discovered that: G = frac{2}{pi}int_0^1frac{dx}{sqrt{1 - x^4
so that
: G = frac{2}{pi}eta(egin{matrix} frac{1}{4}end{matrix}, egin{matrix}frac{1}{4}end{matrix})
where β denotes the
beta function .Relations to other constants
Gauss's constant may be used as a closed-form expression for the
Gamma function at argument 1/4:: Gamma( egin{matrix} frac{1}{4} end{matrix}) = sqrt{ 2G sqrt{ 2pi^3 } }
and since π and Γ(1/4) are
algebraically independent , Gauss's constant is transcendental.Lemniscate constants
Gauss's constant may be used in the definition of the lemniscate constants, the first of which is:
: L_1;=;pi G
and the second constant:
: L_2,,=,,frac{1}{2G}
which arise in finding the
arc length of alemniscate .Other formulas
A formula for "G" in terms of Jacobi theta functions is given by
: G = vartheta_{01}^2(e^{-pi})
as well as the rapidly converging series
: G = sqrt [4] {32}e^{-frac{pi}{3left (sum_{n = -infty}^{infty} (-1)^n e^{-2npi(3n+1)} ight )^2.
The constant is also given by the
infinite product :G = prod_{m = 1}^infty anh^2 left( frac{pi m}{2} ight).
Gauss's constant has
continued fraction [0, 1, 5, 21, 3, 4, 14, ...] .References
*mathworld|urlname=GausssConstant|title=Gauss's Constant
* Sequences A014549 and A053002 inOEIS
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