Theta series of extremal 3-modular even lattice in dimension 18.

Terms

a(0) =1a(1) =0a(2) =648a(3) =17712a(4) =179334a(5) =1043280a(6) =4517208a(7) =15781392a(8) =44619984a(9) =116385552a(10) =272587680a(11) =572320080a(12) =1157871078a(13) =2232349632a(14) =3924968400a(15) =6928383600a(16) =11708537526a(17) =18624904128a(18) =29674012392a(19) =46479068784