

A231982


Decimal expansion of one deg^2 expressed in steradians (sr).


7



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

3,1


COMMENTS

This is the conversion ratio between two solidangle measures: degreesquare's and steradians, applicable to integration infinitesimals. A deg^2 must not be confused with a finite spherical square having one degree side (see A231983, A231984, A231985), just as one steradian must not be confused with the solid angle covered by a spherical square with a side arclength of one radian (see A231986, A231987).


REFERENCES

G. V. Brummelen, Heavenly Mathematics: The Forgotten Art of Spherical Trigonometry, Princeton University Press, 2012, ISBN 9780691148922.


LINKS

Stanislav Sykora, Table of n, a(n) for n = 3..1998
Wikipedia, Steradian
Wikipedia, Square degree


FORMULA

(Pi/180)^2.


EXAMPLE

0.00030461741978670859934674354937889355355906479651977748846954782...


MATHEMATICA

RealDigits[(Pi/180)^2, 10, 120][[1]] (* Harvey P. Dale, Feb 20 2015 *)


CROSSREFS

Cf. A000796 (Pi), A072097 (rad/deg), A019685 (deg/rad), A231981 (inverse, sr/deg^2), A231983 (square with 1 deg side, in sr), A231984 (square with 1 deg side, in deg^2), A231985, A231986 (square with 1 rad side, in sr), A231987.
Sequence in context: A192878 A126826 A231983 * A198575 A112256 A188720
Adjacent sequences: A231979 A231980 A231981 * A231983 A231984 A231985


KEYWORD

nonn,cons,easy


AUTHOR

Stanislav Sykora, Nov 16 2013


STATUS

approved



