Theta series of direct sum of 4 copies of hexagonal lattice.

Terms

a(0) =1a(1) =24a(2) =216a(3) =888a(4) =1752a(5) =3024a(6) =7992a(7) =8256a(8) =14040a(9) =24216a(10) =27216a(11) =31968a(12) =64824a(13) =52752a(14) =74304a(15) =111888a(16) =112344a(17) =117936a(18) =217944a(19) =164640a(20) =220752a(21) =305472a(22) =287712a(23) =292032a(24) =519480a(25) =378024a(26) =474768a(27) =654072