cp's OEIS Frontend

This is a front-end for the Online Encyclopedia of Integer Sequences, made by Christian Perfect. The idea is to provide OEIS entries in non-ancient HTML, and then to think about how they're presented visually. The source code is on GitHub.

Showing 1-2 of 2 results.

A081366 Number of distinct edge lengths in the convex hull of the maximal volume arrangements of n points on a sphere.

Original entry on oeis.org

1, 2, 1, 2, 3, 3, 3, 8, 1, 11, 3, 5, 3, 14, 8, 25, 9, 29, 16, 11, 18, 34, 37, 6
Offset: 4

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Author

Hugo Pfoertner, Mar 19 2003

Keywords

Examples

			a(8)=3 because the corresponding arrangement has 6 edges of length 1.1383499, 8 edges of length 1.264911.. and 4 edges of length 1.4554505, i.e. 3 distinct edge lengths.
		

References

Crossrefs

Symmetry groups of maximal volume arrangements: A081314. Distinct distances for minimal energy configurations: A033177.

A133491 Order of the symmetry group of the (in some cases conjectural) minimal-energy configuration of n identical charged particles confined to the surface of a sphere.

Original entry on oeis.org

12, 24, 12, 48, 20, 16, 12, 16, 4, 120, 4
Offset: 3

Views

Author

Keenan Pepper, Nov 30 2007

Keywords

Comments

a(0), a(1) and a(2) are all infinite, because their symmetry groups are continuous (they contain rotations with arbitrary angles). Actual symmetry groups: 3 D_{3h}, 4 T_{d}, 5 D_{3h}, 6 O_{d}, 7 D_{5h}, 8 D_{4d}, 9 D_{3h}, 10 D_{4h}, 11 D_{1h}, 12 I_{d}, 13 D_{1h}.

Examples

			a(3)=12 because the minimal-energy configuration of 3 charged particles on a sphere is an equilateral triangle on the equator, which has symmetry group D_3h of order 12.
		

Crossrefs

Showing 1-2 of 2 results.