A341332 Decimal expansion of Pi/(2*phi).

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

Offset: 0

Author

Bernard Schott, Feb 09 2021

Keywords

• nonn
• cons

Comments

This is the middle angle (in radians) of the unique right triangle whose angles are in geometric progression; common ratio is phi and the angles are (Pi/(2*phi^2), Pi/(2*phi), Pi/2) in radians, corresponding to approximately (34.377, 55.623, 90) in degrees.

Examples

			0.970805519362733288673432814981347978817334946923024149753694108...
		

Links

• Index entries for transcendental numbers

Crossrefs

Cf. A000796 (Pi), A001622 (phi), A019669 (Pi/2), A180014 (Pi/(2*phi^2)).

Programs

Maple

evalf(Pi/(1+sqrt(5)),150);

Mathematica

RealDigits[Pi/(2*GoldenRatio), 10, 100][[1]] (* Amiram Eldar, Feb 09 2021 *)

PARI

Pi/(1+sqrt(5)) \\ Michel Marcus, Feb 09 2021

Formula

Equals A019669/A001622 = A094881/2 = Pi/(1+sqrt(5)) = (Pi/4) * (sqrt(5)-1).