Thirty-nine perfect numbers and their divisors.
Asadulla, Syed (1986)
International Journal of Mathematics and Mathematical Sciences
Similarity:
Asadulla, Syed (1986)
International Journal of Mathematics and Mathematical Sciences
Similarity:
McDaniel, Wayne L. (1990)
International Journal of Mathematics and Mathematical Sciences
Similarity:
Jan Slowak (1999)
Mathematica Slovaca
Similarity:
Min Tang, Xiao-Zhi Ren, Meng Li (2013)
Colloquium Mathematicae
Similarity:
For a positive integer n, let σ(n) denote the sum of the positive divisors of n. Let d be a proper divisor of n. We call n a near-perfect number if σ(n) = 2n + d, and a deficient-perfect number if σ(n) = 2n - d. We show that there is no odd near-perfect number with three distinct prime divisors and determine all deficient-perfect numbers with at most two distinct prime factors.
Sándor, József (2004)
JIPAM. Journal of Inequalities in Pure & Applied Mathematics [electronic only]
Similarity:
Nielsen, Pace P. (2003)
Integers
Similarity:
Min Tang, Xiaoyan Ma, Min Feng (2016)
Colloquium Mathematicae
Similarity:
For a positive integer n, let σ(n) denote the sum of the positive divisors of n. We call n a near-perfect number if σ(n) = 2n + d where d is a proper divisor of n. We show that the only odd near-perfect number with four distinct prime divisors is 3⁴·7²·11²·19².
De Koninck, Jean-Marie, Ivić, Aleksandar (1998)
Publications de l'Institut Mathématique. Nouvelle Série
Similarity:
Gimbel, Steven, Jaroma, John H. (2003)
Integers
Similarity:
Sándor, József, Kovács, Lehel István (2009)
Acta Universitatis Sapientiae. Mathematica
Similarity:
Tomohiro Yamada (2005)
Colloquium Mathematicae
Similarity:
We show that there is an effectively computable upper bound of odd perfect numbers whose Euler factors are powers of fixed exponent.
G. L. Garg, B. Kumar (1989)
Matematički Vesnik
Similarity: