This site is supported by donations to The OEIS Foundation.

 Hints (Greetings from The On-Line Encyclopedia of Integer Sequences!)
 A019829 Decimal expansion of sine of 20 degrees. 2
 3, 4, 2, 0, 2, 0, 1, 4, 3, 3, 2, 5, 6, 6, 8, 7, 3, 3, 0, 4, 4, 0, 9, 9, 6, 1, 4, 6, 8, 2, 2, 5, 9, 5, 8, 0, 7, 6, 3, 0, 8, 3, 3, 6, 7, 5, 1, 4, 1, 6, 0, 6, 2, 8, 4, 6, 5, 0, 4, 8, 4, 9, 7, 6, 8, 4, 7, 1, 4, 7, 6, 3, 7, 0, 2, 0, 7, 7, 5, 9, 9, 5, 6, 4, 1, 9, 0, 1, 8, 2, 3, 3, 8, 5, 2, 5, 5, 4, 7 (list; constant; graph; refs; listen; history; text; internal format)
 OFFSET 0,1 LINKS FORMULA Equals cos(7*pi/18) = 2F1(13/12,-1/12;1/2;3/4) / 2 . [From R. J. Mathar, Oct 27 2008] MATHEMATICA RealDigits[ Sin[Pi/9], 10, 111]  (* Robert G. Wilson v *) PROG Contribution from Michael B. Porter, Jan 27 2010: (Start) (PARI) /* for x = 20 degrees, sin(9x) = 0 */ /* so sin(x) is a zero of this polynomial */ sin_9(x)=9*x-120*x^3+432*x^5-576*x^7+256*x^9 x=34; y=100; print(3); print(4); for(digits=1, 110, {d=0; y=y*10; while(sin_9((10*x+d)/y) > 0, d++); d--; /* while loop overshoots correct digit */ print(d); x=10*x+d}) (End) CROSSREFS Sequence in context: A123127 A167876 A077451 * A200125 A091528 A096392 Adjacent sequences:  A019826 A019827 A019828 * A019830 A019831 A019832 KEYWORD nonn,cons AUTHOR STATUS approved

Lookup | Welcome | Wiki | Register | Music | Plot 2 | Demos | Index | Browse | More | WebCam
Contribute new seq. or comment | Format | Transforms | Puzzles | Hot | Classics
Recent Additions | More pages | Superseeker | Maintained by The OEIS Foundation Inc.

Content is available under The OEIS End-User License Agreement .