Product t2(q^d); d | 28, where t2 = theta2(q)/(2*q^(1/4)).

Terms

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