Expansion of (theta_3(z)*theta_3(21z)+theta_2(z)*theta_2(21z))^3.

Terms

a(0) =1a(1) =0a(2) =6a(3) =0a(4) =12a(5) =0a(6) =8a(7) =0a(8) =6a(9) =0a(10) =24a(11) =12a(12) =24a(13) =48a(14) =0a(15) =60a(16) =12a(17) =48a(18) =30a(19) =96a(20) =24a(21) =96a(22) =72a(23) =60a(24) =104a(25) =144a(26) =120a(27) =96a(28) =240a(29) =48