login
The OEIS is supported by the many generous donors to the OEIS Foundation.

 

Logo

Year-end appeal: Please make a donation to the OEIS Foundation to support ongoing development and maintenance of the OEIS. We are now in our 59th year, we have over 358,000 sequences, and we’ve crossed 10,300 citations (which often say “discovered thanks to the OEIS”).

Other ways to Give
Hints
(Greetings from The On-Line Encyclopedia of Integer Sequences!)
A353771 Decimal expansion of the gravitational acceleration generated at the center of a face by unit-mass regular tetrahedron with edge length 2 in units where the gravitational constant is G = 1. 4
2, 5, 6, 3, 3, 1, 1, 8, 1, 6, 1, 4, 3, 6, 4, 9, 4, 6, 6, 8, 8, 2, 2, 9, 3, 9, 5, 7, 5, 4, 8, 4, 0, 7, 9, 5, 1, 8, 3, 4, 5, 8, 5, 1, 1, 7, 5, 9, 1, 1, 8, 4, 4, 9, 6, 7, 7, 0, 3, 9, 4, 4, 9, 2, 4, 6, 4, 9, 0, 1, 6, 3, 8, 2, 5, 4, 0, 1, 8, 9, 5, 0, 9, 0, 7, 3, 0, 4, 6, 7, 2, 2, 8, 6, 8, 0, 9, 4, 5, 2, 9, 5, 2, 0, 7 (list; constant; graph; refs; listen; history; text; internal format)
OFFSET

1,1

COMMENTS

The absolute value of the gravitational attraction force between a homogeneous regular tetrahedron with mass M and edge length 2*s and a test particle with mass m located at the tetrahedron's center of face is c*G*M*m/s^2, where G is the gravitational constant (A070058) and c is this constant.

The centers of the faces are the positions where the gravitational field that is generated by the tetrahedron attains its maximum absolute value.

LINKS

Table of n, a(n) for n=1..105.

Murray S. Klamkin, Extreme Gravitational Attraction, Problem 92-5, SIAM Review, Vol. 34, No. 1 (1992), pp. 120-121; Solution, by Carl C. Grosjean, ibid., Vol. 38, No. 3 (1996), pp. 515-520.

Eric Weisstein's World of Physics, Polyhedron Gravitational Force.

Eric Weisstein's World of Physics, Tetrahedron Gravitational Force.

FORMULA

Equals 2*Pi/(3*sqrt(3)) + sqrt(6)*log(sqrt(3) + 2) - 2*sqrt(6)*log(sqrt(3) + sqrt(2))/3.

EXAMPLE

2.56331181614364946688229395754840795183458511759118...

MATHEMATICA

RealDigits[2*Pi/(3*Sqrt[3]) + Sqrt[6]*Log[Sqrt[3] + 2] - 2*Sqrt[6]*Log[Sqrt[3] + Sqrt[2]]/3, 10, 100][[1]]

CROSSREFS

Cf. A070058, A353769, A353770, A353772, A353773.

Sequence in context: A305210 A165501 A274614 * A340859 A336817 A340858

Adjacent sequences: A353768 A353769 A353770 * A353772 A353773 A353774

KEYWORD

nonn,cons

AUTHOR

Amiram Eldar, May 07 2022

STATUS

approved

Lookup | Welcome | Wiki | Register | Music | Plot 2 | Demos | Index | Browse | More | WebCam
Contribute new seq. or comment | Format | Style Sheet | Transforms | Superseeker | Recents
The OEIS Community | Maintained by The OEIS Foundation Inc.

License Agreements, Terms of Use, Privacy Policy. .

Last modified December 4 09:27 EST 2022. Contains 358556 sequences. (Running on oeis4.)