a(n) = Sum_{i|n, j|n, k|n} i*j*k/gcd(i,j,k).

Terms

a(0) =1a(1) =23a(2) =46a(3) =219a(4) =116a(5) =1058a(6) =218a(7) =1507a(8) =883a(9) =2668a(10) =518a(11) =10074a(12) =716a(13) =5014a(14) =5336a(15) =8819a(16) =1208a(17) =20309a(18) =1502a(19) =25404a(20) =10028a(21) =11914a(22) =2186a(23) =69322a(24) =5691a(25) =16468a(26) =12628a(27) =47742a(28) =3452a(29) =122728