Crystal ball sequence for lattice {E_7}*.

Terms

a(0) =1a(1) =57a(2) =995a(3) =8683a(4) =48429a(5) =198677a(6) =653791a(7) =1825719a(8) =4494329a(9) =10016209a(10) =20601723a(11) =39670115a(12) =72292453a(13) =125732205a(14) =210093239a(15) =339085039a(16) =530914929a(17) =809317097a(18) =1204728211a(19) =1755619419a(20) =2509994525a(21) =3527064133a(22) =4879105551a(23) =6653518247a(24) =8955084649a(25) =11908446081a(26) =15660803627a(27) =20384853715