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A367662
Number of regions formed in a hexagon by straight line segments when connecting the n-1 points between each corner that divide each edge into n equal parts to the n-1 points on the edge on the opposite side of the hexagon.
4
1, 6, 54, 252, 780, 1968, 4146, 7662, 13014, 21078, 32562, 46818, 67962, 93048, 123684, 166794, 217380, 271056, 349932, 428250, 523272, 645744, 784794, 918606, 1104966, 1304250, 1515018, 1768974, 2071662, 2317602, 2734242, 3101670, 3486990, 3987774, 4460862, 4978530, 5688804, 6316332
OFFSET
1,2
COMMENTS
Keyword "look" is because of the linked images. - N. J. A. Sloane, Dec 01 2023
LINKS
Scott R. Shannon, Image for n = 2.
Scott R. Shannon, Image for n = 3.
Scott R. Shannon, Image for n = 5.
Scott R. Shannon, Image for n = 8.
Scott R. Shannon, Image for n = 12.
FORMULA
a(n) = A367664(n) - A367663(n) + 1 by Euler's formula.
CROSSREFS
Cf. A367663 (vertices), A367664 (edges), A367665 (k-gons), A355798.
Sequence in context: A260955 A072368 A334881 * A355054 A116138 A227268
KEYWORD
nonn,look
AUTHOR
Scott R. Shannon, Nov 26 2023
STATUS
approved