a(n) = Sum_{k=1..n} k^2*(floor(n/k) - 1).

Terms

a(0) =0a(1) =1a(2) =2a(3) =7a(4) =8a(5) =22a(6) =23a(7) =44a(8) =54a(9) =84a(10) =85a(11) =151a(12) =152a(13) =206a(14) =241a(15) =326a(16) =327a(17) =458a(18) =459a(19) =605a(20) =664a(21) =790a(22) =791a(23) =1065a(24) =1091a(25) =1265a(26) =1356a(27) =1622a(28) =1623a(29) =2023