A320164 Number of integer solutions to a^2 + 2*b^2 + 5*c^2 + 7*d^2 = n.

1, 2, 2, 4, 2, 2, 8, 6, 14, 14, 8, 16, 8, 20, 20, 20, 30, 12, 30, 12, 10, 32, 16, 40, 40, 14, 16, 20, 22, 56, 48, 48, 34, 28, 52, 16, 70, 40, 48, 92, 24, 32, 32, 32, 56, 94, 56, 28, 56, 46, 58, 80, 48, 56, 88, 76, 72, 60, 48, 44, 108, 92, 40, 94, 82, 44, 120, 48, 40

Offset

0,2

Comments

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

Links

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

Formula

G.f.: theta_3(q) * theta_3(q^2) * theta_3(q^5) * theta_3(q^7).

Crossrefs

Cf. A319822, A320163, A320165, A320166, A033722.

Sequence in context: A033722 A320166 A320165 * A113200 A113198 A074130

Adjacent sequences: A320161 A320162 A320163 * A320165 A320166 A320167

Keyword

nonn

Author

Seiichi Manyama, Oct 07 2018

Status

approved