Results 21 to 30 of about 1,177 (152)
Dynamic multi‐objective optimisation of complex networks based on evolutionary computation
IET Networks, EarlyView., 2022 Abstract As the problems concerning the number of information to be optimised is increasing, the optimisation level is getting higher, the target information is more diversified, and the algorithms are becoming more complex; the traditional algorithms such as particle swarm and differential evolution are far from being able to deal with this situation ...
Linfeng Huang
wiley +1 more source
Divisors on graphs, Connected flags, and Syzygies [PDF]
Discrete Mathematics & Theoretical Computer Science, 2013 We study the binomial and monomial ideals arising from linear equivalence of divisors on graphs from the point of view of Gröbner theory. We give an explicit description of a minimal Gröbner basis for each higher syzygy module.
Fatemeh Mohammadi, Farbod Shokrieh
doaj +1 more source
Superpotentials from singular divisors
Journal of High Energy Physics, 2022 We study Euclidean D3-branes wrapping divisors D in Calabi-Yau orientifold compactifications of type IIB string theory. Witten’s counting of fermion zero modes in terms of the cohomology of the structure sheaf O D $$ {\mathcal{O}}_D $$ applies when D is ...
Naomi Gendler +4 more
doaj +1 more source
Thirty-nine perfect numbers and their divisors
International Journal of Mathematics and Mathematical Sciences, 1986 The following results concerning even perfect numbers and their divisors are proved: (1) A positive integer n of the form 2p−1(2p−1), where 2p−1 is prime, is a perfect number; (2) every even perfect number is a triangular number; (3) τ(n)=2p, where τ(n ...
Syed Asadulla
doaj +1 more source
STRUCTURE OF ZERO-DIVISOR GRAPHS ASSOCIATED TO RING OF INTEGER MODULO n [PDF]
Journal of Algebraic Systems, 2023 For a commutative ring $R$ with identity $1\neq 0$, let $Z^{*}(R)=Z(R)\setminus \lbrace 0\rbrace$ be the set of non-zero zero-divisors of $R$, where $Z(R)$ is the set of all zero-divisors of $R$.
Shariefuddin Pirzada +2 more
doaj +1 more source
Nonnegative Inverse Elementary Divisors Problem for Lists with Nonnegative Real Parts
Mathematics, 2020 In this paper, sufficient conditions for the existence and construction of nonnegative matrices with prescribed elementary divisors for a list of complex numbers with nonnegative real part are obtained, and the corresponding nonnegative matrices are ...
Hans Nina +3 more
doaj +1 more source
Journal of Mathematics, 2022 Huppert and Manz have determined the nonsolvable groups whose character degrees are products of at most two prime numbers. In this paper, we change the condition from “degrees of a group are products of at most two prime divisors” to “degrees of all ...
Shitian Liu, Xingzheng Tang
doaj +1 more source
Divisors and square-free divisors involving the floor function [PDF]
Notes on Number Theory and Discrete MathematicsLet τ(n) (respectively, τ#(n)) be the number of divisors (respectively, square free divisors) of natural number n, and let [t] be the integral part of real number t.
B. Feng, J. Wu
doaj +1 more source
ON A SUM INVOLVING CERTAIN ARITHMETIC FUNCTIONS ON PIATETSKI–SHAPIRO AND BEATTY SEQUENCES
Проблемы анализа, 2022 Let 𝑐, 𝛼, 𝛽 ∈ R be such that ...
T. Srichan
doaj +1 more source
A note on h 2,1 of divisors in CY fourfolds. Part I
Journal of High Energy Physics, 2022 In this note, we prove combinatorial formulas for the Hodge number h 2,1 of prime toric divisors in an arbitrary toric hypersurface Calabi-Yau fourfold Y 4.
Manki Kim
doaj +1 more source