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 A320305 a(n) = [q^n] Product_{d | n} theta_3(q^d), where theta_3() is the Jacobi theta function. 2
 1, 2, 2, 2, 4, 2, 14, 2, 8, 4, 2, 2, 56, 2, 2, 2, 26, 2, 104, 2, 60, 6, 14, 2, 452, 4, 2, 4, 68, 2, 582, 2, 74, 2, 14, 2, 1460, 2, 14, 6, 688, 2, 782, 2, 108, 176, 2, 2, 5090, 4, 8, 2, 108, 2, 1640, 2, 940, 6, 2, 2, 38132, 2, 2, 12, 364, 2, 1142, 2, 100, 2, 1266, 2, 62528 (list; graph; refs; listen; history; text; internal format)
 OFFSET 0,2 COMMENTS Also the number of integer solutions (a_1, a_2, ... , a_{d(n)}) to the equation Sum_{d | n} d * a_d^2 = n, where d(n) is the number of divisors of n. LINKS Seiichi Manyama, Table of n, a(n) for n = 0..1000 CROSSREFS Cf. A000005, A000122. Sequence in context: A035580 A135293 A216951 * A064025 A182154 A273875 Adjacent sequences:  A320302 A320303 A320304 * A320306 A320307 A320308 KEYWORD nonn AUTHOR Seiichi Manyama, Oct 10 2018 STATUS approved

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Last modified May 18 09:26 EDT 2021. Contains 343995 sequences. (Running on oeis4.)