a(n) = Sum_{1 <= x_1, x_2 <= n} sigma( n/gcd(x_1, x_2, n) ).

Terms

a(0) =1a(1) =10a(2) =33a(3) =94a(4) =145a(5) =330a(6) =385a(7) =814a(8) =969a(9) =1450a(10) =1441a(11) =3102a(12) =2353a(13) =3850a(14) =4785a(15) =6766a(16) =5185a(17) =9690a(18) =7201a(19) =13630a(20) =12705a(21) =14410a(22) =12673a(23) =26862a(24) =18745a(25) =23530a(26) =26889a(27) =36190a(28) =25201a(29) =47850