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A355840
Number of edges formed in a square by straight line segments when connecting the n+1 points along each edge that divide it into n equal parts to the n+1 points on the edge on the opposite side of the square.
5
8, 64, 316, 852, 2252, 3780, 8140, 12280, 20172, 28592, 45988, 55508, 87588, 107652, 141060, 181312, 246844, 278352, 380108, 424096, 530764, 638564, 799148, 854448, 1082244, 1235048, 1442572, 1612088, 1975908, 2051784, 2565956, 2773616, 3164916, 3566256, 3997652, 4271136, 5137452, 5537756
OFFSET
1,1
COMMENTS
This sequence is similar to A355800 but here the corner vertices of the square are also connected to points on the opposite edge.
See A355838 for images of the squares.
FORMULA
a(n) = A355838(n) + A355839(n) - 1 by Euler's formula.
CROSSREFS
Cf. A355838 (regions), A355839 (vertices), A355841 (k-gons), A355800 (without corner vertices), A290131, A331452, A335678.
Sequence in context: A189690 A188741 A188993 * A223681 A189065 A189190
KEYWORD
nonn
AUTHOR
Scott R. Shannon, Jul 18 2022
STATUS
approved