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A335784 Irregular table read by rows: n-sect the angles of a nonagon (enneagon). Then T(n,k) = number of k-sided polygons in that figure for k >= 3. 4
0, 0, 0, 0, 0, 0, 1, 18, 36, 81, 9, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 1, 126, 36, 180, 135, 18, 45, 9, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 1, 288, 126, 54, 90, 36, 18, 9, 0, 0, 1, 450, 306, 72, 18, 576, 369, 207, 126, 0, 9, 0, 0, 0, 0, 0, 0, 0, 0, 0, 1 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,8

COMMENTS

For n<=200 no polygon has more than 18 edges.

See A335781 for illustrations.

LINKS

Lars Blomberg, Table of n, a(n) for n = 1..2217 (the first 200 rows)

EXAMPLE

The table begins:

0, 0, 0, 0, 0, 0, 1;

18;

36, 81, 9, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 1;

126, 36;

180, 135, 18, 45, 9, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 1;

288, 126, 54;

90, 36, 18, 9, 0, 0, 1;

450, 306, 72, 18;

576, 369, 207, 126, 0, 9, 0, 0, 0, 0, 0, 0, 0, 0, 0, 1;

CROSSREFS

Cf. A332427 (n-sected sides, not angles), A335781 (regions), A335782 (vertices), A335783 (edges).

Sequence in context: A204824 A252424 A327774 * A347889 A115550 A061713

Adjacent sequences:  A335781 A335782 A335783 * A335785 A335786 A335787

KEYWORD

tabf,nonn

AUTHOR

Lars Blomberg, Jun 24 2020

STATUS

approved

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Last modified May 24 14:36 EDT 2022. Contains 354037 sequences. (Running on oeis4.)