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 A339473 #16 Apr 29 2021 22:00:19
%S A339473 18,22,68,76,84,87,93,96,150,162,260,264,268,276,280,284,330,336,348,
%T A339473 354,410,430,588,612,630,635,640,645,655,660,665,670,738,747,765,774,
%U A339473 798,826,1032,1040,1048,1064,1072,1080,1302,1308,1314,1320,1326,1338,1344,1350
%N A339473 Numbers k such that floor(sqrt(k)) divides k^2, but does not divide k.
%e A339473 18 is in the sequence since floor(sqrt(18)) = 4, which does not divide 18, but it does divide 18^2 = 324.
%t A339473 Flatten[Table[If[(1 - Ceiling[n^2/Floor[Sqrt[n]]] + Floor[n^2/Floor[Sqrt[n]]]) (Ceiling[n/Floor[Sqrt[n]]] - Floor[n/Floor[Sqrt[n]]]) == 1, n, {}], {n, 2000}]]
%o A339473 (PARI) isok(k) = (k % sqrtint(k)) && !(k^2 % sqrtint(k)); \\ _Michel Marcus_, Apr 24 2021
%o A339473 (Python)
%o A339473 from math import isqrt
%o A339473 def ok(k): r = isqrt(k); return k % r != 0 and k**2 % r == 0
%o A339473 print(list(filter(ok, range(1, 1351)))) # _Michael S. Branicky_, Apr 24 2021
%Y A339473 Cf. A006446.
%K A339473 nonn
%O A339473 1,1
%A A339473 _Wesley Ivan Hurt_, Apr 24 2021