A232247 Decimal expansion of the arctan of 2/Pi.

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

Offset: 0

Author

Bruno Berselli, Nov 21 2013

Keywords

• nonn
• cons

Examples

			0.56691150494100940508289774672261915380648023909268233575775947204589...
		

Crossrefs

Cf. A060294, A232182.

Programs

Maple

evalf(arctan(2/Pi));

Mathematica

RealDigits[ArcTan[2/Pi], 10, 90][[1]]

PARI

atan(2/Pi) \\ Charles R Greathouse IV, Mar 24 2021

Formula

Equals A019669 - A232182.

Equals Sum_{k>=0} (-1)^k*(2/Pi)^(1+2*k)/(1+2*k).