Product t2(q^d); d | 20, where t2 = theta2(q)/(2*q^(1/4)).

Terms

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