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A331929
The number of regions inside a pentagon formed by the straight line segments mutually connecting all vertices and all points that divide the sides into n equal parts.
17
11, 170, 1161, 3900, 10741, 22380, 44491, 76610, 126336, 194070, 290651, 410860, 577721, 779340, 1035676, 1345030, 1730696, 2176040, 2724036, 3345880, 4087656, 4933200, 5921991, 7018210, 8300896, 9723300, 11339151, 13122120, 15150271, 17345140, 19843056
OFFSET
1,1
COMMENTS
The terms are from numeric computation - no formula for a(n) is currently known.
CROSSREFS
Cf. A331939 (n-gons), A329710 (edges), A330847 (vertices), A007678, A092867, A331452, A331931.
Sequence in context: A362501 A233290 A167245 * A205087 A064182 A139792
KEYWORD
nonn
AUTHOR
EXTENSIONS
a(9) and beyond from Lars Blomberg, May 11 2020
STATUS
approved