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.
%I A366521 #13 Jan 04 2024 18:59:16
%S A366521 1,1,1,2,1,2,1,2,3,2,1,3,1,2,3,2,1,3,1,2,3,2,1,3,5,2,3,2,1,5,1,2,3,2,
%T A366521 5,6,1,2,3,5,1,6,1,2,5,2,1,6,7,5,3,2,1,6,5,7,3,2,1,6,1,2,7,2,5,6,1,2,
%U A366521 3,7,1,6,1,2,5,2,7,6,1,5,3,2,1,7,5,2,3,2,1,6,7,2,3,2,5,6,1,7,3,10
%N A366521 Largest squarefree divisor of n which is <= sqrt(n).
%H A366521 Andrew Howroyd, <a href="/A366521/b366521.txt">Table of n, a(n) for n = 1..10000</a>
%t A366521 Table[Last[Select[Divisors[n], # <= Sqrt[n] && SquareFreeQ[#] &]], {n, 100}]
%o A366521 (PARI) a(n) = {my(m=1); fordiv(n, d, if(d^2 <= n && issquarefree(d), m=max(m,d))); m} \\ _Andrew Howroyd_, Oct 11 2023
%Y A366521 Cf. A007947, A033676, A089384, A366522.
%K A366521 nonn
%O A366521 1,4
%A A366521 _Ilya Gutkovskiy_, Oct 11 2023