a(n) = sigma_6(n^2)/sigma_3(n^2).

Terms

a(0) =1a(1) =57a(2) =703a(3) =3641a(4) =15501a(5) =40071a(6) =117307a(7) =233017a(8) =512461a(9) =883557a(10) =1770231a(11) =2559623a(12) =4824613a(13) =6686499a(14) =10897203a(15) =14913081a(16) =24132657a(17) =29210277a(18) =47039023a(19) =56439141a(20) =82466821a(21) =100903167a(22) =148023723a(23) =163810951a(24) =242203001a(25) =275002941a(26) =373584043