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%I #8 May 26 2020 10:25:36
%S 3,6,16,45,111,230,448,769,1229,1858,2860,4007,5737,7724,10115,13074,
%T 17172,21454,27288,33332,40413,48944,59594,70213,82983,97608,113672,
%U 131032,152986,174088,201090,228295,258467,292726,328080,365633,412291,460834,512016
%N 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.
%C See the links in A332953 for images of the triangles.
%H Lars Blomberg, <a href="/A333026/b333026.txt">Table of n, a(n) for n = 1..70</a>
%Y Cf. A332953 (regions), A333025 (n-gons), A333027 (edges), A007678, A092867, A331452, A331911, A332357, A332358.
%K nonn
%O 1,1
%A _Scott R. Shannon_ and _N. J. A. Sloane_, Mar 05 2020
%E a(16) and beyond from _Lars Blomberg_, May 26 2020