A320305 a(n) = [q^n] Product_{d | n} theta_3(q^d), where theta_3() is the Jacobi theta function.

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

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: A135293 A216951 A366628 * A064025 A182154 A273875

Adjacent sequences: A320302 A320303 A320304 * A320306 A320307 A320308

Keyword

nonn

Author

Seiichi Manyama, Oct 10 2018

Status

approved