OFFSET
1,1
REFERENCES
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. Minoli, New Results For Hyperperfect Numbers, Abstracts American Math. Soc., October 1980, Issue 6, Vol. 1, pp. 561.
J. Roberts, Lure of the Integers, Math. Assoc. America, 1992, p. 177.
N. J. A. Sloane and Simon Plouffe, The Encyclopedia of Integer Sequences, Academic Press, 1995 (includes this sequence).
LINKS
Donovan Johnson, Table of n, a(n) for n = 1..10000
Mariano Garcia, Hyperperfect Numbers with Five and Six Different Prime Factors, Fib. Quart. 42, no. 4, Nov. 2004, pp. 292-294.
J. S. McCranie, A study of hyperperfect numbers, J. Int. Seqs. Vol. 3 (2000) #P00.1.3.
D. Minoli and Robert Bear, Hyperperfect Numbers, Pi Mu Epsilon Journal, Fall 1975, pp. 153-157.
Daniel Minoli, W. Nakamine, Mersenne Numbers Rooted On 3 For Number Theoretic Transforms, 1980 IEEE International Conf. on Acoust., Speech and Signal Processing.
Daniel Minoli, Issues In Non-Linear Hyperperfect Numbers, Mathematics of Computation, Vol. 34, No. 150, April 1980, pp. 639-645.
D. Minoli, Structural Issues For Hyperperfect Numbers, Fibonacci Quarterly, Feb. 1981, Vol. 19, No. 1, pp. 6-14.
Herman J. J. te Riele, Hyperperfect numbers with three different prime factors, Math. Comp. 36 (1981), 297-298.
Eric Weisstein's World of Mathematics, Hyperperfect Number.
MATHEMATICA
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 *)
CROSSREFS
KEYWORD
nonn,nice
AUTHOR
EXTENSIONS
More terms from Jud McCranie, Oct 15 1997
STATUS
approved