a(n) = Sum_{k<=n} A007955(k) * A007955(k) = Sum_{k<=n} A007955(k)^2, where A007955(m) = product of divisors of m.
A174939
a(n) = Sum_{k<=n} A007955(k) * A007955(k) = Sum_{k<=n} A007955(k)^2, where A007955(m) = product of divisors of m.
Terms
- a(0) =1a(1) =5a(2) =14a(3) =78a(4) =103a(5) =1399a(6) =1448a(7) =5544a(8) =6273a(9) =16273a(10) =16394a(11) =3002378a(12) =3002547a(13) =3040963a(14) =3091588a(15) =4140164a(16) =4140453a(17) =38152677a(18) =38153038a(19) =102153038a(20) =102347519a(21) =102581775a(22) =102582304a(23) =110177896480a(24) =110177912105a(25) =110178369081a(26) =110178900522a(27) =110660790826a(28) =110660791667
External references
- oeis: A174939