• 제목/요약/키워드: Nielsen number

검색결과 38건 처리시간 0.03초

A relative nielsen number in coincidence theory

  • Jang, Chan-Gyu;Lee, Sik
    • 대한수학회지
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    • 제32권2호
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    • pp.171-181
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    • 1995
  • Nielsen coincidence theory is concerned with the estimation of a lower bound for the number of coincidences of two maps $f,g: X \longrightarrow Y$. For this purpose the so-called Nielsen number N(f,g) is introduced, which is a lower bound for the number of coincidences ([1]). The relative Nielsen number N(f : X,A) in the fixed point theory is introduced in [3], which is a lower bound for the number of fixed points for all maps in the relative homotopy class of f:(X,A) $\longrightarrow$ (X,A), and its estimation is given in [5].

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A relative root Nielsen number

  • Yang, Ki-Yeol
    • 대한수학회논문집
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    • 제11권1호
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    • pp.245-252
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    • 1996
  • The relative Nielsen number N(f;X,A) was introduced in 1986. It gives us a better, and ideally sharp, lower bound for the minimum number MF[f;X,A] of fixed points in the homotopy class of the map $f;(X,A) \to (X,A)$. Similarly, we also can think about the Nielsen map $f:(X,A) \to (X,A)$. Similarly, we also can be think about the Nielsen root theory. In this paper, we introduce a relative root Nielsen number N(f;X,A,c) of $f:(X,A) \to (Y,B)$ and show some basic properties.

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THE MOD H NIELSEN NUMBER

  • Kim, Seung Won
    • 충청수학회지
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    • 제22권2호
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    • pp.229-234
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    • 2009
  • Let f : $X{\rightarrow}X$ be a self-map of a connected finite polyhedron X. In this short note, we say that the mod H Nielsen number $N_H(f)$ is well-defined without the algebraic condition $ f_{\pi}(H)\;{\subseteq}H$ and that $N_H(f)$ is the same as the q-Nielsen number $N_q(f)$ in any case.

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THE NIELSEN ROOT NUMBET FOR THE COMPLEMENT

  • Yang, Ki-Yeol
    • 한국수학교육학회지시리즈B:순수및응용수학
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    • 제8권1호
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    • pp.61-69
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    • 2001
  • The purpose of this paper is to introduce the Nielsen root number for the complement N(f:X-A,c) which shares such properties with the Nielsen root number N(f;c) as lower bound and homotopy invariance.

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A NOTE ON NIELSEN TYPE NUMBERS

  • Lee, Seoung-Ho
    • 대한수학회논문집
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    • 제25권2호
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    • pp.263-271
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    • 2010
  • The Reidemeister orbit set plays a crucial role in the Nielsen type theory of periodic orbits, such as the Reidemeister set does in Nielsen fixed point theory. In this paper, using Heath and You's methods on Nielsen type numbers, we show that these numbers can be evaluated by the set of essential orbit classes under suitable hypotheses, and obtain some formulas in some special cases.

A RELATIVE NAIELSEN COINCIDENCE NUMBER FOR THE COMPLEMENT, I

  • Lee, Seoung-Ho
    • 대한수학회지
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    • 제33권4호
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    • pp.709-716
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    • 1996
  • Nielsen coincidence theory is concerned with the determinatin of a lower bound of the minimal number MC[f,g] of coincidence points for all maps in the homotopy class of a given map (f,g) : X $\to$ Y. The Nielsen Nielsen number $N_R(f,g)$ (similar to [9]) is introduced in [3], which is a lower bound for the number of coincidence points in the relative homotopy class of (f,g) and $N_R(f,g) \geq N(f,g)$.

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A NIELSEN TYPE NUMBER OF FIBRE PRESERVING MAPS

  • Lee, Seoung Ho
    • 대한수학회논문집
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    • 제28권2호
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    • pp.361-369
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    • 2013
  • We introduce a Nielsen type number of a fibre preserving map, and show that it is a lower bound for the number of $n$-orbits in the homotopy class. Under suitable conditions we show that it is equal to the Nielsen type relative essential $n$-orbit number. We also give necessary and sufficient conditions for it and the essential $n$-orbit number to coincide.

NIELSEN TYPE NUMBERS FOR PERIODIC POINTS ON THE COMPLEMENT

  • LIM, IN TAIK
    • 호남수학학술지
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    • 제24권1호
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    • pp.75-86
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    • 2002
  • A Nielsen number $\bar{N}(f:X-A)$ is a homotopy invariant lower bound for the number of fixed points on X-A where X is a compact connected polyhedron and A is a connected subpolyhedron of X. This number is extended to Nielsen type numbers $\bar{NP_{n}}(f:X-A)$ of least period n and $\bar{N{\phi}_{n}}(f:X-A)$ of the nth iterate on X-A where the subpolyhedron A of a compact connected polyhedron X is no longer path connected.

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The Product Formula For Nielsen Root number

  • Yang, Ki-Yeol
    • 대한수학회논문집
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    • 제15권2호
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    • pp.357-370
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    • 2000
  • In [6], Cheng-Ye You gave a condition equivalent to the Nielsen number product formula for fiber maps. And Jerzy Jezierski also gave a similar condition for coincidences of fiber maps. The main purpose of this paper is to find the condition for which holds the product formula for Nielsen root numbers N(f;a) = N(f;a) N(fb;a).

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