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A208899 Decimal expansion of sqrt(5)/3 . 1
7, 4, 5, 3, 5, 5, 9, 9, 2, 4, 9, 9, 9, 2, 9, 8, 9, 8, 8, 0, 3, 0, 5, 7, 8, 8, 9, 5, 7, 7, 0, 9, 2, 0, 7, 8, 4, 8, 0, 2, 0, 6, 1, 1, 9, 8, 7, 0, 5, 0, 8, 5, 7, 4, 7, 5, 6, 9, 6, 5, 7, 4, 8, 4, 7, 0, 1, 7, 3, 6, 4, 1, 8, 7, 9, 2, 6, 8, 2, 9, 9, 8, 0, 4, 8, 0, 4, 8, 0, 2, 7, 9, 2, 9, 2, 7, 4, 2, 4, 9 (list; constant; graph; refs; listen; history; text; internal format)
OFFSET

0,1

COMMENTS

Equals the absolute value of the cosine of the dihedral angle between two adjacent faces of the regular icosahedron.

LINKS

Ivan Panchenko, Table of n, a(n) for n = 0..1000

Wikipedia, Exsphere

FORMULA

Equals A002163/3 = 20*A020837/3

EXAMPLE

0.7453559924...

MATHEMATICA

RealDigits[Sqrt[5]/3, 10, 120][[1]] (* Harvey P. Dale, Jul 03 2013 *)

CROSSREFS

Sequence in context: A011475 A180078 A019685 * A087491 A019899 A085662

Adjacent sequences:  A208896 A208897 A208898 * A208900 A208901 A208902

KEYWORD

nonn,cons,easy

AUTHOR

R. J. Mathar, Mar 03 2012

STATUS

approved

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Last modified December 10 13:38 EST 2016. Contains 279004 sequences.