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 A066245 #12 Sep 26 2019 09:05:45 %S A066245 3,6,10,34,50,91,222,364,1485,6640,18579,775698,1035507,1706366, %T A066245 46388515,75714802 %N A066245 Floor(|x*sin(x)|)-perfect numbers, where f-perfect numbers for an arithmetical function f are defined in A066218. %H A066245 J. Pe, <a href="http://jlpe.tripod.com/gpn/fperfect.htm">On a Generalization of Perfect Numbers</a>, J. Rec. Math., 31(3) (2002-2003), 168-172. %e A066245 Let f(n) = floor(|x*sin(x)|). Then f(6) = 1 = 0+1+0 = f(3)+f(2)+f(1); so 6 is a term of the sequence. %t A066245 f[x_] := Floor[Abs[x*Sin[x]]]; Select[ Range[2, 10^4], 2 * f[ # ] == Apply[ Plus, Map[ f, Divisors[ # ] ] ] & ] %Y A066245 Cf. A066218. %K A066245 nonn,more %O A066245 1,1 %A A066245 _Joseph L. Pe_, Dec 19 2001 %E A066245 a(11)-a(16) from _Amiram Eldar_, Sep 26 2019