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A268683
Decimal expansion of (sqrt(2) - 1)/2.
4
2, 0, 7, 1, 0, 6, 7, 8, 1, 1, 8, 6, 5, 4, 7, 5, 2, 4, 4, 0, 0, 8, 4, 4, 3, 6, 2, 1, 0, 4, 8, 4, 9, 0, 3, 9, 2, 8, 4, 8, 3, 5, 9, 3, 7, 6, 8, 8, 4, 7, 4, 0, 3, 6, 5, 8, 8, 3, 3, 9, 8, 6, 8, 9, 9, 5, 3, 6, 6, 2, 3, 9, 2, 3, 1, 0, 5, 3, 5, 1, 9, 4, 2, 5, 1, 9, 3
OFFSET
0,1
COMMENTS
This is the maximum increase in mass-energy a particle can carry away from a neutral rotating (Kerr) black hole via the Penrose process.
Apart from leading digits the same as A174968, A157214 and A010503. - R. J. Mathar, Feb 24 2016
REFERENCES
Subrahmanyan Chandrasekhar, The Mathematical Theory of Black Holes, Oxford (1983), pp. 368-369.
LINKS
Stijn J. van Tongeren, Rotating black holes (2009).
Wikipedia, Penrose process
EXAMPLE
0.20710678118654752440084436210484903928483593768847403658833986899536623...
MATHEMATICA
RealDigits[(Sqrt[2] - 1) / 2, 10, 90] [[1]] (* Vincenzo Librandi, Feb 20 2016 *)
PROG
(PARI) (sqrt(2)-1)/2
(Magma) (Sqrt(2)-1)/2 // Vincenzo Librandi, Feb 20 2016
CROSSREFS
Sequence in context: A022897 A192496 A156442 * A174968 A254445 A346670
KEYWORD
nonn,cons,easy
AUTHOR
EXTENSIONS
More digits from Jon E. Schoenfield, Mar 15 2018
STATUS
approved