A335781
a(n) is the number of regions formed by n-secting the angles of a nonagon (enneagon).
Original entry on oeis.org
1, 18, 127, 162, 388, 468, 154, 846, 1288, 1422, 1945, 2106, 2827, 1260, 3700, 3870, 4798, 4950, 5995, 6318, 4879, 7524, 8830, 9108, 10387, 10764, 12331, 8730, 13933, 14454, 16147, 16434, 18325, 18846, 16363, 20718, 23077, 23472, 25516, 26154, 28486, 23274
Offset: 1
A335782
a(n) is the number of vertices formed by n-secting the angles of a nonagon (enneagon).
Original entry on oeis.org
9, 19, 135, 118, 396, 379, 135, 712, 1296, 1243, 1953, 1891, 2835, 955, 3708, 3556, 4806, 4600, 6003, 5914, 4860, 7084, 8838, 8623, 10395, 10234, 12339, 7786, 13941, 13825, 16155, 15769, 18333, 18136, 16344, 19981, 23085, 22672, 25524, 25309, 28494, 22069
Offset: 1
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.
Original entry on oeis.org
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
Offset: 1
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;
Showing 1-3 of 3 results.
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