Crystal ball sequence for E_7 lattice.

Terms

a(0) =1a(1) =127a(2) =3025a(3) =28911a(4) =162417a(5) =652431a(6) =2086241a(7) =5659295a(8) =13561889a(9) =29504095a(10) =59400241a(11) =112234255a(12) =201127185a(13) =344628207a(14) =568250433a(15) =906272831a(16) =1403829569a(17) =2119308095a(18) =3127077265a(19) =4520566831a(20) =6415719601a(21) =8954837583a(22) =12310843425a(23) =16691978463a(24) =22346958689a(25) =29570609951