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

Author

Seiichi Manyama, Oct 10 2018

Keywords

• nonn

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.