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 A176357 Partial sums of A036403. 0
 1, 127, 4054, 37210, 134325, 776241, 1313848, 5536128, 7280823, 28243653, 32246894, 74873810 (list; graph; refs; listen; history; text; internal format)
 OFFSET 1,2 COMMENTS 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. LINKS FORMULA a(n) = SUM[i=1..n] A036403(i). EXAMPLE a(4) = 1 + 126 + 3927 + 33156 = 37210 = 2 * 5 * 61^2. CROSSREFS Cf. A006600, A036403. Sequence in context: A144969 A114535 A215611 * A201071 A137789 A268663 Adjacent sequences:  A176354 A176355 A176356 * A176358 A176359 A176360 KEYWORD nonn AUTHOR Jonathan Vos Post, Apr 15 2010 STATUS approved

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Last modified August 18 08:57 EDT 2019. Contains 326077 sequences. (Running on oeis4.)