Number of points in interior of n-th crystal ball in E_8 lattice.

Terms

a(0) =1a(1) =241a(2) =26641a(3) =338401a(4) =2240161a(5) =10242001a(6) =36638641a(7) =109907521a(8) =288653761a(9) =683158321a(10) =1486914001a(11) =3020862241a(12) =5793372001a(13) =10579330321a(14) =18522042481a(15) =31261968001a(16) =51096647041a(17) =81176500081a(18) =125741512081a(19) =190404140641a(20) =282484116001a(21) =411401129041a(22) =589131731761