A195628 Decimal expansion of arctan(4).

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

Offset

1,2

Links

G. C. Greubel, Table of n, a(n) for n = 1..10000

Formula

Equals arcsin(4/sqrt(17)) = arccos(1/sqrt(17)). - Amiram Eldar, Jul 11 2023

Example

arctan(4) = 1.3258176636680324650592392104284756311844406013...

Mathematica

r = 4;
N[ArcTan[r], 100]
RealDigits[%]  (* A195628 *)
N[ArcCot[r], 100]
RealDigits[%]  (* A195727 *)
N[ArcSec[r], 100]
RealDigits[%]  (* A195731 *)
N[ArcCsc[r], 100]
RealDigits[%]  (* A195621 *)

Prog

(Magma) SetDefaultRealField(RealField(125)); Arctan(4); // G. C. Greubel, Apr 13 2023
(SageMath) numerical_approx( arctan(4), digits=125) # G. C. Greubel, Apr 13 2023

Crossrefs

Cf. A195727, A195731, A195621.

Sequence in context: A094894 A089334 A016649 * A124422 A223544 A132776

Adjacent sequences: A195625 A195626 A195627 * A195629 A195630 A195631

Keyword

nonn,cons

Author

Clark Kimberling, Sep 23 2011

Status

approved