Expansion of (theta_3(z)*theta_3(13z) + theta_2(z)*theta_2(13z)).

Terms

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