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 A066242 #16 Oct 06 2023 21:23:32 %S A066242 2,18,20,32,45,63 %N A066242 The floor((log(x))^2)-perfect numbers, where f-perfect numbers for an arithmetical function f are defined in A066218. %H A066242 J. Pe, <a href="https://www.numeratus.net/fperfect/fperfect.html">On a Generalization of Perfect Numbers</a>, J. Rec. Math., 31(3) (2002-2003), 168-172. %e A066242 Let f(n) = floor((log(x))^2). Then f(18) = 8 = 4+3+1+0+0 = f(9)+f(6)+f(3)f(2)+f(1); so 18 is a term of the sequence. %t A066242 f[x_ ] := Floor[Log[x]^2]; Select[ Range[2, 10^5], 2 * f[ # ] == Apply[ Plus, Map[ f, Divisors[ # ] ] ] & ] %K A066242 nonn,more %O A066242 1,1 %A A066242 _Joseph L. Pe_, Dec 19 2001