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A248508
Decimal expansion of K_J = 2 e/h (Josephson constant) in units of A s^2 kg^{-1} m^{-2} in the 2019 SI system of units.
8
4, 8, 3, 5, 9, 7, 8, 4, 8, 4, 1, 6, 9, 8, 3, 6, 3, 2, 4, 4, 7, 6, 5, 8, 2, 8, 5, 0, 5, 4, 5, 2, 8, 1, 3, 5, 3, 5, 3, 3, 5, 1, 1, 8, 6, 6, 0, 0, 4, 0, 1, 4, 4, 6, 0, 9, 6, 9, 7, 4, 9, 9, 2, 0, 3, 2, 0, 4, 1, 7, 9, 7, 8, 0, 6, 8, 0, 4, 0, 8, 2, 8, 0, 9, 1, 7, 4, 6, 0, 5, 5, 5, 4, 0, 9, 3, 0, 2, 4, 5
OFFSET
15,1
COMMENTS
The value of K(J-90) is 483597.9 * 10^9 Hz V^-1 based on measurements in 1990. - Ralf Steiner, Jan 03 2019
The value of K(J) is 2 * e / h = 483597.848416... * 10^9 Hz V^-1 based on SI definitions (effective on May 20, 2019). - Ralf Steiner, Jan 03 2019
From Wolfdieter Lang, May 20 2019: (Start)
For the seven units of the 2019 SI system see A322415 with references.
Here only the Planck constant h = 6.62607015*10^{-34} J s, with J = kg m^2 s^(-2), and the elementary charge e = 1.602176634*10^{-19} C, with C = A s are used.
The 1990 definition of Volt with symbol V is K_{J-90} = (V s)^{-1}, where s^(-1) = Δν_{Cs}/9192631770. (End)
FORMULA
Equals 2 * A081823 / A003676.
EXAMPLE
K_J = 2*e/h = 4.83597848416983632447658285054528135353351186600401446096974992032041797... * 10^14 A s^2/(kg m^2). - Wolfdieter Lang, May 20 2019
MATHEMATICA
RealDigits[2*(1.602176634`100*10^(-19))/(6.62607015`100*10^(-34))][[1]]
PROG
(PARI) 21362355120000000000000/44173801 \\ Charles R Greathouse IV, Jul 16 2023
CROSSREFS
Cf. A003676 (h), A081823 (e), A248507 (inverse).
Sequence in context: A234001 A248946 A232808 * A362530 A065191 A229988
KEYWORD
nonn,cons,easy
AUTHOR
EXTENSIONS
Updated by Ralf Steiner, Jan 03 2019
STATUS
approved