

A341764


The number of edges on a 2 by 1 ellipse formed by the straight line segments mutually connecting all points formed by dividing the ellipse into 2n equal angle sectors from its origin.


3



1, 8, 42, 148, 426, 984, 2022, 3604, 6138, 9492, 14642, 21108, 29902, 40728, 54786, 71604, 92722, 117384, 147578, 181810, 223782, 270808, 326262, 388308, 460446, 540424, 632322, 733364, 848318, 973732, 1115422, 1269108, 1441122, 1626888, 1833406, 2055444, 2300822, 2563544, 2852358, 3160050, 3497562
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OFFSET

1,2


COMMENTS

The terms are from numeric computation  no formula for a(n) is currently known.
See A341688 for a description of the ellipse and images of the regions, and A341762 for images of the vertices.


LINKS

Table of n, a(n) for n=1..41.
Wikipedia, Ellipse.


FORMULA

a(n) = A341688(n) + A341762(n)  1.


CROSSREFS

Cf. A341688 (regions), A341762 (vertices), A341800 (ngons), A007678, A092867, A255011, A331929, A331931, A333075.
Sequence in context: A027903 A231069 A319235 * A256861 A287221 A119965
Adjacent sequences: A341761 A341762 A341763 * A341765 A341766 A341767


KEYWORD

nonn


AUTHOR

Scott R. Shannon and N. J. A. Sloane, Feb 19 2021


STATUS

approved



