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Number of integer solutions to a^2 + 2*b^2 + 4*c^2 + 6*d^2 = n.
11

%I #11 Oct 08 2018 05:37:22

%S 1,2,2,4,4,4,10,12,10,14,16,12,24,28,12,20,28,16,26,36,8,24,48,24,30,

%T 42,28,40,72,28,32,60,34,60,64,24,28,76,36,56,80,40,60,84,72,52,96,48,

%U 72,86,42,80,56,52,82,96,36,72,112,60,120,124,60,84,124,56,96,132,32

%N Number of integer solutions to a^2 + 2*b^2 + 4*c^2 + 6*d^2 = n.

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

%H Seiichi Manyama, <a href="/A320195/b320195.txt">Table of n, a(n) for n = 0..10000</a>

%F G.f.: theta_3(q) * theta_3(q^2) * theta_3(q^4) * theta_3(q^6).

%Y Cf. A320193, A320194, A320196, A033720, A320197, A320198, A320199, A320200, A320201, A320202.

%K nonn

%O 0,2

%A _Seiichi Manyama_, Oct 07 2018