a(n) = floor(n/2) * floor(n^2/2).

Terms

a(0) =0a(1) =0a(2) =2a(3) =4a(4) =16a(5) =24a(6) =54a(7) =72a(8) =128a(9) =160a(10) =250a(11) =300a(12) =432a(13) =504a(14) =686a(15) =784a(16) =1024a(17) =1152a(18) =1458a(19) =1620a(20) =2000a(21) =2200a(22) =2662a(23) =2904a(24) =3456a(25) =3744a(26) =4394a(27) =4732a(28) =5488a(29) =5880