A377277 Decimal expansion of 12*arctan(sqrt(2)).

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

Offset

2,3

Comments

Dehn invariant of a truncated tetrahedron with unit edge and (negated) of a regular tetrahedron with unit edge.

Links

Table of n, a(n) for n=2..91.

Eric Weisstein's World of Mathematics, Dehn Invariant.

Eric Weisstein's World of Mathematics, Regular Tetrahedron.

Eric Weisstein's World of Mathematics, Truncated Tetrahedron.

Index entries for transcendental numbers

Formula

Equals 12*A195696 = A377296/2.

Example

11.463799417494111337966285230189093050920976340...

Mathematica

First[RealDigits[12*ArcTan[Sqrt[2]], 10, 100]] (* or *)
First[RealDigits[PolyhedronData["Tetrahedron", "DehnInvariant"], 10, 100]]

Prog

(PARI) 12*atan(sqrt(2)) \\ Charles R Greathouse IV, Nov 20 2024

Crossrefs

Cf. A195696, A377296.

Sequence in context: A273819 A276761 A073000 * A378221 A198113 A264962

Adjacent sequences: A377274 A377275 A377276 * A377278 A377279 A377280

Keyword

nonn,cons,easy

Author

Paolo Xausa, Oct 23 2024

Status

approved