Expansion of (chi(-x) * chi(-x^19))^2 in powers of x where chi() is a Ramanujan theta function.

Terms

a(0) =1a(1) =-2a(2) =1a(3) =-2a(4) =4a(5) =-4a(6) =5a(7) =-6a(8) =9a(9) =-12a(10) =13a(11) =-16a(12) =21a(13) =-26a(14) =29a(15) =-36a(16) =46a(17) =-54a(18) =62a(19) =-76a(20) =94a(21) =-108a(22) =126a(23) =-150a(24) =179a(25) =-210a(26) =239a(27) =-282a(28) =335a(29) =-384