A333026 The number of vertices formed on an isosceles triangle by straight line segments mutually connecting all vertices and all points that divide the two equal length sides into n equal parts; the base of the triangle contains no points other than its vertices.

3, 6, 16, 45, 111, 230, 448, 769, 1229, 1858, 2860, 4007, 5737, 7724, 10115, 13074, 17172, 21454, 27288, 33332, 40413, 48944, 59594, 70213, 82983, 97608, 113672, 131032, 152986, 174088, 201090, 228295, 258467, 292726, 328080, 365633, 412291, 460834, 512016

Offset

1,1

Comments

See the links in A332953 for images of the triangles.

Links

Lars Blomberg, Table of n, a(n) for n = 1..70

Crossrefs

Cf. A332953 (regions), A333025 (n-gons), A333027 (edges), A007678, A092867, A331452, A331911, A332357, A332358.

Sequence in context: A192676 A202846 A107269 * A391963 A086811 A106361

Adjacent sequences: A333023 A333024 A333025 * A333027 A333028 A333029

Keyword

nonn

Author

Scott R. Shannon and N. J. A. Sloane, Mar 05 2020

Extensions

a(16) and beyond from Lars Blomberg, May 26 2020

Status

approved