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A102912 Decimal expansion of a close approximation to the Ramanujan constant. 4
2, 6, 2, 5, 3, 7, 4, 1, 2, 6, 4, 0, 7, 6, 8, 7, 4, 3, 9, 9, 9, 9, 9, 9, 9, 9, 9, 9, 9, 9, 2, 5, 1, 1, 2, 3, 8, 7, 5, 9, 3, 6, 7, 9, 9, 8, 0, 0, 9, 5, 4, 4, 1, 7, 3, 6, 7, 9, 1, 0, 2, 2, 7, 7, 1, 6, 6, 3, 5, 3, 5, 7, 0, 9, 1, 7, 6, 1, 3, 7, 3, 3, 3, 4, 1, 0, 0, 6, 2, 8, 1, 0, 4, 9, 2, 7, 6, 5, 1, 0, 4, 2, 4, 8, 7 (list; constant; graph; refs; listen; history; text; internal format)
OFFSET

18,1

COMMENTS

First differs from Ramanujan's constant (A060295) at a(33). - Omar E. Pol, Jun 26 2012

Kontsevich & Zagier give also exp(3*log(640320)) = 2.62537412640768000... as a close approximation to the Ramanujan constant. - Jean-Fran├žois Alcover, Jun 22 2015

LINKS

Table of n, a(n) for n=18..122.

M. Kontsevich and D. Zagier, Periods, Institut des Hautes Etudes Scientifiques 2001 IHES/M/01/22

Eric Weisstein's World of Mathematics, Ramanujan Constant

EXAMPLE

262537412640768743.999999999999251123875936799800954417367910227716...

MATHEMATICA

RealDigits[ Root[ #^3 - 6#^2 + 4# - 2 &, 1]^24 - 24, 10, 111][[1]]

CROSSREFS

Cf. A060295.

Sequence in context: A221188 A220532 A060295 * A064850 A151853 A268766

Adjacent sequences:  A102909 A102910 A102911 * A102913 A102914 A102915

KEYWORD

cons,nonn

AUTHOR

Eric W. Weisstein, Jan 17 2005

STATUS

approved

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Last modified December 7 13:07 EST 2016. Contains 278875 sequences.