On the number of perfect binary quadratic forms.

Aicardi, Francesca

Displaying similar documents to “On the number of perfect binary quadratic forms.”

Counting perfect matchings in polyominoes with an application to the dimer problem

P. John, H. Sachs, H. Zernitz (1987)

Applicationes Mathematicae

Similarity:

A Unified Theory of Perfect and Related Functions

M. N. Mukherjee, S. Raychaudhuri (1993)

Matematički Vesnik

Similarity:

C-closed functions

G. L. Garg, B. Kumar (1989)

Matematički Vesnik

Similarity:

The number of 1-factors in some polyhexes.

Tošić, Ratko, Vojvodić, Dušan (2000)

Novi Sad Journal of Mathematics

Similarity:

Odd perfect numbers of a special form

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.

On near-perfect and deficient-perfect numbers

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.

A Property Of The Number Of Perfect Matchings Of A Graph

Ivan Gutman (1991)

Publications de l'Institut Mathématique

Similarity:

Cyclotomic quadratic forms

François Sigrist (2000)

Journal de théorie des nombres de Bordeaux

Similarity:

Voronoï ’s algorithm is a method for obtaining the complete list of perfect $n$ -dimensional quadratic forms. Its generalization to $G$ -forms has the advantage of running in a lower-dimensional space, and furnishes a finite, and complete, classification of $G$ -perfect forms ( $G$ is a finite subgroup of $G L (n, ℤ))$ . We study the standard, $φ (m)$ -dimensional irreducible representation of the cyclic group $C_{m}$ of order $m$ , and give the, often new, densest $G$ -forms. Perfect cyclotomic forms are completely classified...

On the minimal points of perfect quadratic forms.

R.A. Rankin (1964)

Mathematische Zeitschrift

Similarity:

A basic approach to the perfect extensions of spaces

Giorgio Nordo (1997)

Commentationes Mathematicae Universitatis Carolinae

Similarity:

In this paper we generalize the notion of of a Tychonoff space to a generic extension of any space by introducing the concept of . This allow us to simplify the treatment in a basic way and in a more general setting. Some [S $_{1}$ ], [S $_{2}$ ], and [D]’s results are improved and new characterizations for perfect (Hausdorff) extensions of spaces are obtained.

On a sum of divisors problem.

De Koninck, Jean-Marie, Ivić, Aleksandar (1998)

Publications de l'Institut Mathématique. Nouvelle Série

Similarity: