Results 31 to 40 of about 542,394 (229)
Primitive abundant and weird numbers with many prime factors [PDF]
, 2018 We give an algorithm to enumerate all primitive abundant numbers (briefly, PANs) with a fixed $\Omega$ (the number of prime factors counted with their multiplicity), and explicitly find all PANs up to $\Omega=6$, count all PANs and square-free PANs up to
Amato, Gianluca +3 more
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Understanding the Influence of DEM Vertical Accuracy on Sentinel-1 Geolocation Performance [PDF]
The International Archives of the Photogrammetry, Remote Sensing and Spatial Information SciencesDigital Elevation Models (DEMs) are fundamental for ensuring the geolocation accuracy of Synthetic Aperture Radar (SAR) imagery, as vertical errors in elevation data propagate into horizontal displacements.
S. Oğuzhanoğlu, F. Sunar
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On a thin set of integers involving the largest prime factor function
International Journal of Mathematics and Mathematical Sciences, 2003 For each integer n≥2, let P(n) denote its largest prime factor. Let S:={n≥2:n does not divide P(n)!} and S(x):=#{n≤x:n∈S}. Erdős (1991) conjectured that S is a set of zero density.
Jean-Marie De Koninck, Nicolas Doyon
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Environment International, 2019 Preterm birth (PTB) can give rise to significant neonatal morbidity and mortality, as well as children’s long-term health defects. Many studies have illustrated the associations between ambient air pollution exposure during gestational periods and PTB ...
Zhe Sun +9 more
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Squarefree smooth numbers and Euclidean prime generators [PDF]
, 2017 We show that for each prime p > 7, every residue mod p can be represented by a squarefree number with largest prime factor at most p. We give two applications to recursive prime generators akin to the one Euclid used to prove the infinitude of primes ...
Booker, Andrew R., Pomerance, Carl
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Elephants and their woodland habitats in northern Botswana
Pachyderm, 1999 The elephant population in northern Botswana (estimated to be some 80,000)is considered the largest remaining 'herd' in Africa. This paper looks at this population and its habitat in terms of its current status, the their food and water requirements ...
Raphael Ben-Shahar
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MOMENTS OF THE SMARANDACHE FUNCTION [PDF]
, 1999 Given a positive integer n, let P(n) denote the largest prime factor of nand S(n) denote the smallest integer m such that n divides m
Finch, Steven R.
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A generalization of primitive sets and a conjecture of Erdős
Discrete Analysis, 2020 A generalization of primitive sets and a conjecture of Erdős, Discrete Analysis 2020:16, 13 pp. Call a set $A$ of integers greater than 1 _primitive_ if no element of $A$ divides any other. How dense can a primitive set be?
Tsz Ho Chan +2 more
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On the σ-Length of Maximal Subgroups of Finite σ-Soluble Groups
Mathematics, 2020 Let σ={σi:i∈I} be a partition of the set P of all prime numbers and let G be a finite group. We say that G is σ-primary if all the prime factors of |G| belong to the same member of σ. G is said to be σ-soluble if every chief factor of G is σ-primary, and
Abd El-Rahman Heliel +2 more
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