A140273 Decimal expansion of 180*arctan(3*sqrt(15)/29)/Pi.

2, 1, 8, 3, 3, 6, 7, 7, 9, 9, 1, 8, 2, 4, 4, 5, 2, 1, 0, 0, 3, 8, 5, 0, 6, 1, 7, 6, 0, 0, 5, 4, 5, 7, 1, 7, 9, 5, 9, 8, 2, 9, 3, 5, 4, 1, 0, 3, 8, 2, 3, 8, 3, 6, 0, 6, 1, 5, 8, 8, 0, 2, 1, 9, 6, 0, 4, 8, 5, 2, 2, 4, 4, 6, 0, 9, 0, 7, 9, 6, 3, 0, 8, 8, 6, 5, 4, 1, 9, 2, 2, 8, 3, 0, 2, 0, 0, 2, 5, 8, 7, 9, 4, 1, 2

Offset

2,1

Comments

The Brocard angle in degrees of the obtuse scalene triangle with sides of lengths 2, 3 and 4, the scalene triangle with least integer side lengths. See formulas in the Weisstein link.

Links

Table of n, a(n) for n=2..106.

Eric Weisstein's World of Mathematics, Brocard Angle.

Formula

180*arctan(3*sqrt(15)/29)/Pi = 180*A140272/Pi = 180*arctan(4*A140239/29)/Pi.

Example

21.8336779918244521003850617600545717959829354103823836061588021960485224460...

Mathematica

RealDigits[180 ArcTan[(3Sqrt[15])/29]/Pi, 10, 120][[1]] (* Harvey P. Dale, Dec 15 2012 *)

Prog

(PARI) 180*atan(3*sqrt(15)/29)/Pi

Crossrefs

Cf. A140272, A140239.

Sequence in context: A123235 A176052 A351560 * A378807 A021462 A082834

Adjacent sequences: A140270 A140271 A140272 * A140274 A140275 A140276

Keyword

cons,nonn

Author

Rick L. Shepherd, May 16 2008

Status

approved