Results 61 to 70 of about 12,930 (215)
Combinatorics of Positroids [PDF]
Discrete Mathematics & Theoretical Computer Science, 2009 Recently Postnikov gave a combinatorial description of the cells in a totally-nonnegative Grassmannian. These cells correspond to a special class of matroids called positroids.
Suho Oh
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A simple recurrence formula for the number of rooted maps on surfaces by edges and genus [PDF]
Discrete Mathematics & Theoretical Computer Science, 2014 We establish a simple recurrence formula for the number $Q_g^n$ of rooted orientable maps counted by edges and genus. The formula is a consequence of the KP equation for the generating function of bipartite maps, coupled with a Tutte equation, and it was
Sean Carrell, Guillaume Chapuy
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Spaceborne and spaceborn: Physiological aspects of pregnancy and birth during interplanetary flight
Experimental Physiology, EarlyView.Abstract Crewed interplanetary return missions that are on the planning horizon will take years, more than enough time for initiation and completion of a pregnancy. Pregnancy is viewed as a sequence of processes – fertilization, blastocyst formation, implantation, gastrulation, placentation, organogenesis, gross morphogenesis, birth and neonatal ...
Arun V. Holden
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Teaching of probability theory and combinatorics at secondary schools
Lietuvos Matematikos Rinkinys, 2004 The topics of probability theory and combinatorics were brought into curricula of Lithuanian secondary schools ten years ago. The problems of teaching and actual situation of apprehension of concepts of probability theory and combinatorics are analyzed.
Eugenijus Stankus
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Statistics of Feynman amplitudes in ϕ 4-theory
Journal of High Energy Physics, 2023 The amplitude of subdivergence-free logarithmically divergent Feynman graphs in ϕ 4-theory in 4 spacetime dimensions is given by a single number, the Feynman period. We numerically compute the periods of 1.3 million completed graphs, this represents more
Paul-Hermann Balduf
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Worst-Case to Average-Case Reductions via Additive Combinatorics [PDF]
, 2022 Vahid R. Asadi +3 more
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Some bounds related to the 2‐adic Littlewood conjecture
Mathematika, Volume 72, Issue 2, April 2026.Abstract For every irrational real α$\alpha$, let M(α)=supn⩾1an(α)$M(\alpha) = \sup _{n\geqslant 1} a_n(\alpha)$ denote the largest partial quotient in its continued fraction expansion (or ∞$\infty$, if unbounded). The 2‐adic Littlewood conjecture (2LC) can be stated as follows: There exists no irrational α$\alpha$ such that M(2kα)$M(2^k \alpha)$ is ...
Dinis Vitorino, Ingrid Vukusic
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Simple 3‐Designs of PSL ( 2 , 2 n ) With Block Size 13
Journal of Combinatorial Designs, Volume 34, Issue 3, Page 119-138, March 2026.ABSTRACT This paper focuses on the investigation of simple 3‐( 2 n + 1 , 13 , λ ) designs admitting PSL ( 2 , 2 n ) as an automorphism group. Such designs arise from the orbits of 13‐element subsets under the action of PSL ( 2 , 2 n ) on the projective line X = GF ( 2 n ) ∪ { ∞ }, and any union of these orbits also forms a 3‐design.
Takara Kondo, Yuto Nogata
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Continuous dependence and differentiation of solutions of finite difference equations
International Journal of Mathematics and Mathematical Sciences, 1991 Conditions are given for the continuity and differentiability of solutions of initial value problems and boundary value problems for the nth order finite difference equation, u(m+n)=f(m,u(m),u(m+1),…,u(m+n−1)),m∈ℤ.
Johnny Henderson, Linda Lee
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