

A248424


Decimal expansion of the length of a parsec (meters), prior to its redefinition in August 2015.


2



3, 0, 8, 5, 6, 7, 7, 5, 8, 1, 4, 6, 7, 1, 9, 1, 5, 8, 0, 7, 8, 7, 1, 6, 1, 6, 0, 9, 3, 5, 9, 9, 6, 1, 2, 5, 1, 4, 8, 5, 3, 0, 1, 8, 4, 6, 0, 0, 2, 1, 3, 2, 8, 6, 3, 2, 4, 6, 4, 1, 0, 9, 7, 3, 4, 9, 2, 3, 1, 9, 1, 6, 1, 7, 7, 7, 9, 2, 1, 3, 9, 0, 2, 7, 8, 9, 0, 0, 0, 3, 5
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OFFSET

17,1


COMMENTS

The distance for which 1 AU (approximately the mean radius of the Earth's orbit around the Sun) subtends an angle of 1 arcsecond.
The value is exactly 149597870700 m / tan(Pi/(180*3600)) since it is defined in terms of the astronomical unit, whose length was defined in 2012, see A163103.  M. F. Hasler, Oct 14 2014
This constant is algebraic of degree 86400.  Charles R Greathouse IV, Oct 31 2014
In 2015 the parsec was redefined to be exactly 648000/π astronomical units, so this sequence no longer gives the current value of a parsec, which is now given in A292525.  M. F. Hasler, Sep 18 2017
Although the definition has changed, this sequence is preserved in the OEIS for historical reasons.  N. J. A. Sloane, Oct 14 2017


LINKS

Table of n, a(n) for n=17..107.
International Astronomical Union, 2012 Resolution B1
J. S. Calcut, Rationality and the Tangent Function, as of Oct 12 2006.
Wikipedia, Parsec


FORMULA

Equals approximately A217572 * A163103.


EXAMPLE

1 parsec = 149597870700 m / tan(Pi/(180*3600)) ~ 3.085677581 * 10^16 meters.


MATHEMATICA

RealDigits[ 149597870700 / Tan[Pi/648000], 10, 111][[1]] (* Robert G. Wilson v, Nov 17 2014 *)


PROG

(PARI) 149597870700/tan(Pi/180/3600) \\ Then use eval(Vec(Str(%))) or digits(%\.1^99) to get the digits.  M. F. Hasler, Oct 14 2014


CROSSREFS

Cf. A163103, A217572, A248645, A292525.
Sequence in context: A201577 A223854 A333567 * A292525 A275975 A201665
Adjacent sequences: A248421 A248422 A248423 * A248425 A248426 A248427


KEYWORD

nonn,cons


AUTHOR

Arkadiusz Wesolowski, Oct 06 2014


EXTENSIONS

More terms from M. F. Hasler, Oct 14 2014


STATUS

approved



