On representations of a number as a sum of three triangles
Displaying 181 – 200 of 375
On restricted m-ary partitions.
Gunnar Dirdal (1975)
Mathematica Scandinavica
On Rowland's sequence.
Chamizo, Fernando, Raboso, Dulcinea, Ruiz-Cabello, Serafín (2011)
The Electronic Journal of Combinatorics [electronic only]
On semiregular digraphs of the congruence
Lawrence Somer, Michal Křížek (2007)
Commentationes Mathematicae Universitatis Carolinae
We assign to each pair of positive integers and a digraph whose set of vertices is and for which there is a directed edge from to if . The digraph is semiregular if there exists a positive integer such that each vertex of the digraph has indegree or 0. Generalizing earlier results of the authors for the case in which , we characterize all semiregular digraphs when is arbitrary.
On sequences of ±1's defined by binary patterns [Book]
David W. Boyd, Janice Cook, Patrick Morton (1989)
On sets characterizing additive arithmetical functions, I
Robert Freud (1979)
Acta Arithmetica
On sets characterizing additive arithmetical functions, I
Robert Freud (1980)
Acta Arithmetica
On sets S.
P. Laborde (1970)
Gaceta Matemática
On Shanks' algorithm for computing the continued fraction of .
Jackson, Terence, Matthews, Keith (2002)
Journal of Integer Sequences [electronic only]
On short sums of certain multiplicative functions.
Bordellès, Olivier (2002)
JIPAM. Journal of Inequalities in Pure & Applied Mathematics [electronic only]
On solutions of polynomial congruences
Sanoli Gun (2010)
Acta Arithmetica
On some aspects of multiplicative arithmetic functions
Subrahmanyasastri, V.V., Hanumanthachari, J. (1979)
Portugaliae mathematica
On some extensions of Jordan's arithmetic functions.
Andrica, Dorin, Piticari, Mihai (2004)
Acta Universitatis Apulensis. Mathematics - Informatics
On some Markov matrices arising from the generalized Collatz mapping
R. Buttsworth, K. Matthews (1990)
Acta Arithmetica
On some modifications of two theorems of Erdős
Katalin Kovács (1998)
Acta Mathematica et Informatica Universitatis Ostraviensis
On some new congruences for generalized Bernoulli numbers
Shigeru Kanemitsu, Jerzy Urbanowicz, Nianliang Wang (2012)
Acta Arithmetica
On some number-theoretic sums introduced by Jacobsthal
Helge Tverberg (2012)
Acta Arithmetica
On some problems of Mąkowski-Schinzel and Erdős concerning the arithmetical functions ϕ and σ
Florian Luca, Carl Pomerance (2002)
Colloquium Mathematicae
Let σ(n) denote the sum of positive divisors of the integer n, and let ϕ denote Euler's function, that is, ϕ(n) is the number of integers in the interval [1,n] that are relatively prime to n. It has been conjectured by Mąkowski and Schinzel that σ(ϕ(n))/n ≥ 1/2 for all n. We show that σ(ϕ(n))/n → ∞ on a set of numbers n of asymptotic density 1. In addition, we study the average order of σ(ϕ(n))/n as well as its range. We use similar methods to prove a conjecture of Erdős that ϕ(n-ϕ(n)) < ϕ(n)...
On some rings of arithmetical functions.
Bhattacharjee, D. (1999)
Georgian Mathematical Journal
On some special quartic reciprocity laws
Emma Lehmer (1972)
Acta Arithmetica