A320153 Number of integer solutions to a^2 + 2*b^2 + 2*c^2 + 7*d^2 = n.

1, 2, 4, 8, 6, 8, 8, 2, 16, 18, 24, 36, 24, 24, 16, 24, 26, 32, 60, 40, 40, 48, 8, 12, 56, 34, 72, 80, 34, 44, 24, 64, 44, 80, 96, 48, 102, 60, 40, 72, 72, 80, 144, 84, 52, 104, 40, 96, 120, 82, 92, 96, 120, 76, 80, 80, 84, 120, 136, 120, 72, 120, 64, 194, 102

Offset: 0

Author

Seiichi Manyama, Oct 06 2018

Keywords

• nonn

Comments

a(n) > 0 for n >= 0.

Links

• Seiichi Manyama, Table of n, a(n) for n = 0..10000

Crossrefs

Cf. A320149, A320150, A236924, A320151, A320152.

Formula

G.f.: theta_3(q) * theta_3(q^2)^2 * theta_3(q^7).