cp's OEIS Frontend

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.

A066365 f-perfect numbers, where f(m) = sigma(m)-m.

This page as a plain text file.
%I A066365 #15 Aug 06 2025 18:30:29
%S A066365 1,1134,1476,1530,16600,282555
%N A066365 f-perfect numbers, where f(m) = sigma(m)-m.
%C A066365 f-perfect numbers for an arithmetical function f is defined in A066218.
%C A066365 Also, numbers m such that 3*sigma(m)-2*m = A007429(m). - _Max Alekseyev_, Jul 30 2025
%H A066365 J. Pe, <a href="https://vixra.org/abs/2503.0165">On a Generalization of Perfect Numbers</a>, J. Rec. Math., 31(3) (2002-2003), 168-172.
%t A066365 f[x_] := Abs[DivisorSigma[1, x] - x]; Select[ Range[2, 10^6], 2 * f[ # ] == Apply[ Plus, Map[ f, Divisors[ # ] ] ] & ]
%Y A066365 Cf. A007429, A066218.
%K A066365 nonn,more
%O A066365 1,2
%A A066365 _Joseph L. Pe_, Dec 21 2001
%E A066365 Edited and a(1)=1 inserted by _Max Alekseyev_, Jul 30 2025