A066986 Integers of the form (Product_{i=1..k} sigma(i))/(Product_{i=1..k} phi(i)) = A066780(k)/A001088(k).
1, 3, 6, 21, 189, 252, 945, 361179, 1083537
Offset: 1
This is a front-end for the Online Encyclopedia of Integer Sequences, made by Christian Perfect. The idea is to provide OEIS entries in non-ancient HTML, and then to think about how they're presented visually. The source code is on GitHub.
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