%I #5 Jun 18 2024 00:18:44

%S 1,127,4054,37210,134325,776241,1313848,5536128,7280823,28243653,

%T 32246894,74873810

%N Partial sums of A036403.

%C Partial sums of number of equilateral triangles whose vertices (whether connected by lines or not) lie at intersection points resulting from drawing lines connecting every pair of vertices of a regular 3n-gon (and extending beyond the polygon).

%F a(n) = Sum_{i=1..n} A036403(i).

%e a(4) = 1 + 126 + 3927 + 33156 = 37210 = 2 * 5 * 61^2.

%Y Cf. A006600, A036403.

%K nonn,more

%O 1,2

%A _Jonathan Vos Post_, Apr 15 2010