Expansion of e.g.f. theta_3^(13/2).

Terms

a(0) =1a(1) =13a(2) =143a(3) =1287a(4) =9321a(5) =62205a(6) =598455a(7) =7702695a(8) =78423345a(9) =647284365a(10) =9370936575a(11) =174468068775