a(n) = Sum_{k=1..n-1} k^8*sigma(k)*sigma(n-k).

Terms

a(0) =0a(1) =1a(2) =771a(3) =28552a(4) =540563a(5) =3830364a(6) =29209978a(7) =119337536a(8) =490114881a(9) =1659932478a(10) =4961414965a(11) =12516905184a(12) =33139873949a(13) =77515802840a(14) =156374512326a(15) =344012784128a(16) =669604434612