Number of sublattices of index n in generic 4-dimensional lattice.

Terms

a(0) =1a(1) =15a(2) =40a(3) =155a(4) =156a(5) =600a(6) =400a(7) =1395a(8) =1210a(9) =2340a(10) =1464a(11) =6200a(12) =2380a(13) =6000a(14) =6240a(15) =11811a(16) =5220a(17) =18150a(18) =7240a(19) =24180a(20) =16000a(21) =21960a(22) =12720a(23) =55800a(24) =20306a(25) =35700a(26) =33880a(27) =62000a(28) =25260a(29) =93600