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A019890 Decimal expansion of sine of 81 degrees. 0
9, 8, 7, 6, 8, 8, 3, 4, 0, 5, 9, 5, 1, 3, 7, 7, 2, 6, 1, 9, 0, 0, 4, 0, 2, 4, 7, 6, 9, 3, 4, 3, 7, 2, 6, 0, 7, 5, 8, 4, 0, 6, 8, 6, 1, 5, 8, 9, 8, 8, 0, 4, 3, 4, 9, 2, 3, 9, 0, 4, 8, 0, 1, 6, 3, 8, 0, 7, 2, 9, 3, 5, 9, 6, 9, 7, 1, 2, 7, 3, 5, 7, 1, 1, 9, 6, 3, 0, 3, 7, 9, 9, 9, 8, 8, 6, 7, 7, 8 (list; constant; graph; refs; listen; history; internal format)
OFFSET

0,1

LINKS

Anonymous, Exact trigonometric constants, Wikipedia

FORMULA

Equals cos(Pi/20)=sqrt[(1+A019881)/2] = sqrt(1-A019818^2)= sqrt[5-sqrt(5)]*[sqrt(5)+sqrt{5+2*sqrt(5)}]/(4*sqrt(5)] - R. J. Mathar (mathar(AT)strw.leidenuniv.nl), Jun 18 2006

CROSSREFS

Sequence in context: A090671 A132673 A107927 * A066666 A021905 A200688

Adjacent sequences:  A019887 A019888 A019889 * A019891 A019892 A019893

KEYWORD

nonn,cons

AUTHOR

N. J. A. Sloane (njas(AT)research.att.com).

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Last modified February 16 08:13 EST 2012. Contains 205893 sequences.