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A179050
Decimal expansion of 5/(2*sqrt(5+2*sqrt(5))), area of regular pentagram with base edge length 1.
2
8, 1, 2, 2, 9, 9, 2, 4, 0, 5, 8, 2, 2, 6, 5, 8, 1, 5, 3, 8, 9, 6, 7, 8, 5, 3, 0, 5, 3, 7, 8, 3, 6, 1, 6, 2, 3, 8, 7, 2, 5, 8, 6, 7, 8, 8, 0, 3, 6, 8, 7, 7, 5, 0, 7, 6, 9, 5, 1, 1, 7, 9, 7, 8, 4, 1, 6, 8, 2, 2, 5, 2, 4, 0, 1, 8, 6, 2, 3, 7, 0, 8, 0, 6, 7, 1, 9, 3, 3, 8, 6, 1, 7, 4, 1, 2, 6, 2, 6, 2, 0, 4, 2, 5, 9
OFFSET
0,1
COMMENTS
An algebraic number of degree 4: the smaller positive root of 16x^4 - 200x^2 + 125. - Charles R Greathouse IV, Dec 03 2012
EXAMPLE
0.81229924058226581538967853053783616238725867880368775076951179784168...
MATHEMATICA
a=1; area=5/(2*Sqrt[5+2*Sqrt[5]]); RealDigits[N[area, 20]]
PROG
(PARI) 5/sqrt(20+8*sqrt(5)) \\ Charles R Greathouse IV, Dec 03 2012
KEYWORD
nonn,cons,easy
AUTHOR
EXTENSIONS
Offset corrected, keyword:cons inserted by R. J. Mathar, Jun 28 2010
Name corrected by Charles R Greathouse IV, Dec 03 2012
STATUS
approved