Expansion of (theta_3(z)*theta_3(20z)+theta_2(z)*theta_2(20z)).

Terms

a(0) =1a(1) =0a(2) =0a(3) =0a(4) =2a(5) =0a(6) =0a(7) =0a(8) =0a(9) =0a(10) =0a(11) =0a(12) =0a(13) =0a(14) =0a(15) =0a(16) =2a(17) =0a(18) =0a(19) =0a(20) =0a(21) =4a(22) =0a(23) =0a(24) =0a(25) =0a(26) =0a(27) =0a(28) =0a(29) =4