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A003678
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Decimal expansion of the SI unit c (speed of light in vacuum), c = 299792458 meters/second.
(Formerly M1912)
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76
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OFFSET
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9,1
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COMMENTS
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Since 1983, the speed of light has been defined to be exactly 299792458 m/s. - Ron Marcinski (ronmarcinski(AT)hotmail.com), Apr 18 2002
General context: Within current metrological systems (SI + IAU definitions), several physics constants have been "assigned" immutable values. They thus became metrological reference points, no longer subject to experimental assessment. These should not be confused with "conventional" values of some empirical quantities (such as Josephson's constant) used in applied metrology, but not assigned, and therefore subject to possible future revisions.
Assigned metrological constants [before the inception of the 2019 SI, which introduced some changes, see below for references] and some of their combinations that appear in the OEIS include the speed of light (this sequence); magnetic permeability of vacuum (A019694); electric permittivity of vacuum (A081799); characteristic impedance of vacuum (A213610); standard gravity acceleration (A072915), standard atmosphere (A213611), Julian year (A213612), Gregorian year (A213613) and the light-year (A213614), all in basic SI units.
(End)
Prime factors of this number are 2^1, 7^1, 73^1, 293339^1. - John W. Nicholson, Jun 15 2014
c is also the speed of gravity. - Omar E. Pol, Jun 23 2017
In the 2019 SI system of units (see the second BIPM link, and A322415) one of the seven defining constants is c = 299792458 m/s. - Wolfdieter Lang, Feb 12 2019 [corrected by Ivan Panchenko, May 20 2019]
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REFERENCES
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CRC Handbook for Chemistry and Physics, 75th edition, (1994-1995), Page 1-1.
H. J. Fischbeck and K. Fischbeck, Formulas. Facts and Constants, Springer-Verlag, NY, 2nd ed., 1987.
R. F. Fox and T. P. Hill, An exact value for Avogadro's number, American Scientist, 95 (No. 2, 2007), 104-107.
K. R. Lang, Astrophysical Data: Planets and Stars, Springer-Verlag, NY, 1991.
N. J. A. Sloane and Simon Plouffe, The Encyclopedia of Integer Sequences, Academic Press, 1995 (includes this sequence).
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LINKS
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FORMULA
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c = 299792458 m/s (equals 299792.458 km/s).
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MATHEMATICA
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CROSSREFS
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More assigned constants: A003676 (h), A230458 (Δν_{Cs}), A081823 (e), A322578 (N_A), A070063 (k), A021687 (1/K_{cd}); A182999 (c^2), A183000 (c^3), A183001 (c^4), A019694, A081799, A213610, A072915, A213611, A213612, A213613, A213614.
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KEYWORD
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AUTHOR
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STATUS
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approved
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