Theta series of quadratic form (or lattice) with Gram matrix [ 3, 1; 1, 4 ].

Terms

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