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

Terms

a(0) =1a(1) =8a(2) =22a(3) =57a(4) =91a(5) =185a(6) =247a(7) =402a(8) =545a(9) =775a(10) =917a(11) =1379a(12) =1573a(13) =1995a(14) =2455a(15) =3106a(16) =3428a(17) =4377a(18) =4775a(19) =5909a(20) =6753a(21) =7727a(22) =8301a(23) =10331a(24) =11230a(25) =12564a(26) =13904a(27) =15990a(28) =16888a(29) =19908