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 A007592 M5113 #46 Feb 16 2025 08:32:31
%S A007592 21,301,325,697,1333,1909,2041,2133,3901,10693,16513,19521,24601,
%T A007592 26977,51301,96361,130153,159841,163201,176661,214273,250321,275833,
%U A007592 296341,306181,389593,486877,495529,542413,808861,1005421,1005649,1055833,1063141,1232053
%N A007592 Hyperperfect numbers: k = m*(sigma(k) - k - 1) + 1 for some m > 1.
%D A007592 D. Minoli, Sufficient Forms For Generalized Perfect Numbers, Ann. Fac. Sciences, Univ. Nation. Zaire, Section Mathem; Vol. 4, No. 2, Dec 1978, pp. 277-302.
%D A007592 D. Minoli, New Results For Hyperperfect Numbers, Abstracts American Math. Soc., October 1980, Issue 6, Vol. 1, pp. 561.
%D A007592 J. Roberts, Lure of the Integers, Math. Assoc. America, 1992, p. 177.
%D A007592 N. J. A. Sloane and Simon Plouffe, The Encyclopedia of Integer Sequences, Academic Press, 1995 (includes this sequence).
%H A007592 Donovan Johnson, <a href="/A007592/b007592.txt">Table of n, a(n) for n = 1..10000</a>
%H A007592 Mariano Garcia, <a href="https://web.archive.org/web/2024*/https://www.fq.math.ca/Papers1/42-4/quartgarcia04_2004.pdf">Hyperperfect Numbers with Five and Six Different Prime Factors</a>, Fib. Quart. 42, no. 4, Nov. 2004, pp. 292-294.
%H A007592 J. S. McCranie, <a href="https://cs.uwaterloo.ca/journals/JIS/VOL3/mccranie.html">A study of hyperperfect numbers</a>, J. Int. Seqs. Vol. 3 (2000) #P00.1.3.
%H A007592 D. Minoli and Robert Bear, <a href="http://www.pme-math.org/journal/issues/PMEJ.Vol.6.No.3.pdf">Hyperperfect Numbers</a>, Pi Mu Epsilon Journal, Fall 1975, pp. 153-157.
%H A007592 Daniel Minoli, W. Nakamine, <a href="http://dx.doi.org/10.1109/ICASSP.1980.1170906">Mersenne Numbers Rooted On 3 For Number Theoretic Transforms</a>, 1980 IEEE International Conf. on Acoust., Speech and Signal Processing.
%H A007592 Daniel Minoli, <a href="http://dx.doi.org/10.1090/S0025-5718-1980-0559206-9">Issues In Non-Linear Hyperperfect Numbers</a>, Mathematics of Computation, Vol. 34, No. 150, April 1980, pp. 639-645.
%H A007592 D. Minoli, <a href="https://web.archive.org/web/2024*/https://www.fq.math.ca/Scanned/19-1/minoli.pdf">Structural Issues For Hyperperfect Numbers</a>, Fibonacci Quarterly, Feb. 1981, Vol. 19, No. 1, pp. 6-14.
%H A007592 Herman J. J. te Riele, <a href="http://dx.doi.org/10.1090/S0025-5718-1981-0595066-9">Hyperperfect numbers with three different prime factors</a>, Math. Comp. 36 (1981), 297-298.
%H A007592 Eric Weisstein's World of Mathematics, <a href="https://mathworld.wolfram.com/HyperperfectNumber.html">Hyperperfect Number.</a>
%t A007592 hpnQ[n_]:=Module[{den=DivisorSigma[1,n]-n-1,c},If[den!=0,c=(n-1)/den, c=Pi];IntegerQ[c]&&c>1]; Select[Range[1250000],hpnQ] (* _Harvey P. Dale_, Aug 11 2012 *)
%Y A007592 See A034897 (for m >= 1).
%K A007592 nonn,nice
%O A007592 1,1
%A A007592 _N. J. A. Sloane_
%E A007592 More terms from _Jud McCranie_, Oct 15 1997