Results 1 to 10 of about 21 (20)
Estudo comparativo entre o aço SAE 1566 e o aço SAE 15B36 aplicados na produção de lâminas utilizadas na agricultura [PDF]
, 2022 Willian Moreira Alves
openaire +2 more sources
Generating functions for a lattice path model introduced by Deutsch
Special Matrices, 2021 The lattice path model suggested by E. Deutsch is derived from ordinary Dyck paths, but with additional down-steps of size −3, −5, −7, . . . . For such paths, we find the generating functions of them, according to length, ending at level i, both, when ...
Prodinger Helmut
doaj +1 more source
On Generalized Jacobsthal and Jacobsthal–Lucas Numbers
Annales Mathematicae Silesianae, 2022 Jacobsthal numbers and Jacobsthal–Lucas numbers are some of the most studied special integer sequences related to the Fibonacci numbers. In this study, we introduce one parameter generalizations of Jacobsthal numbers and Jacobsthal–Lucas numbers.
Bród Dorota, Michalski Adrian
doaj +1 more source
Special Matrices, 2021 Given a real number a ≥ 1, let Kn(a) be the set of all n × n unit lower triangular matrices with each element in the interval [−a, a]. Denoting by λn(·) the smallest eigenvalue of a given matrix, let cn(a) = min {λ n(YYT) : Y ∈ Kn(a)}.
Altınışık Ercan
doaj +1 more source
On idempotent stable range 1 matrices
Special Matrices, 2022 We characterize the idempotent stable range 1, 2 × 2 matrices over commutative rings and in particular the integral matrices with this property. Several special cases and examples complete the subject.
Călugăreanu Grigore, Pop Horia F.
doaj +1 more source
Some combinatorial matrices and their LU-decomposition
Special Matrices, 2020 Three combinatorial matrices were considered and their LU-decompositions were found. This is typically done by (creative) guessing, and the proofs are more or less routine calculations.
Prodinger Helmut
doaj +1 more source
Analele Stiintifice ale Universitatii Ovidius Constanta: Seria Matematica, 2022 A ring is called negative clean if the negative (i.e., the additive inverse) of each clean element is also clean. Clean rings are negative clean.
Călugăreanu Grigore, Pop Horia F.
doaj +1 more source
Multiple gcd-closed sets and determinants of matrices associated with arithmetic functions
Open Mathematics, 2016 Let f be an arithmetic function and S= {x1, …, xn} be a set of n distinct positive integers. By (f(xi, xj)) (resp. (f[xi, xj])) we denote the n × n matrix having f evaluated at the greatest common divisor (xi, xj) (resp. the least common multiple [xi, xj]
Hong Siao, Hu Shuangnian, Hong Shaofang
doaj +1 more source
The integer cp-rank of 2 × 2 matrices
Special Matrices, 2019 We show the cp-rank of an integer doubly nonnegative 2 × 2 matrix does not exceed 11.
Laffey Thomas, Šmigoc Helena
doaj +1 more source
Inverses and eigenvalues of diamondalternating sign matrices
Special Matrices, 2014 An n × n diamond alternating sign matrix (ASM) is a (0, +1, −1)-matrix with ±1 entries alternatingand arranged in a diamond-shaped pattern. The explicit inverse (for n even) or generalized inverse (for nodd) of a diamond ASM is derived.
Catral Minerva +3 more
doaj +1 more source