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.
?(Divisible[j, #] &)]; Set[{a[n], j}, {k, k}], {n, 3, nn}]; Array[a, nn] (* _Michael De Vlieger has authored 0 sequences.