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Number of integer solutions to a^2 + b^2 + 2*c^2 + 8*d^2 = n.
9

%I #11 Oct 07 2018 03:33:22

%S 1,4,6,8,12,8,8,16,8,20,36,24,48,40,16,48,24,40,78,40,72,64,24,48,32,

%T 60,84,80,96,40,48,64,24,96,108,96,156,72,40,112,48,104,192,88,144,

%U 168,48,96,96,100,186,144,168,136,80,144,64,160,180,120,288,104,64,208

%N Number of integer solutions to a^2 + b^2 + 2*c^2 + 8*d^2 = n.

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

%H Seiichi Manyama, <a href="/A320130/b320130.txt">Table of n, a(n) for n = 0..10000</a>

%F G.f.: theta_3(q)^2 * theta_3(q^2) * theta_3(q^8).

%Y Cf. A097057, A320124, A320125, A320126, A320127, A320128, A320131, A320132, A320133, A320134, A320135, A320136.

%K nonn

%O 0,2

%A _Seiichi Manyama_, Oct 06 2018