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%I #2 Mar 30 2012 18:40:52
%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). The subsequence of primes in this partial sum begins: 127, x.
%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
%O 1,2
%A _Jonathan Vos Post_, Apr 15 2010
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