منابع مشابه
Concordance and 1-loop clovers
We show that surgery on a connected clover (or clasper) with at least one loop preserves the concordance class of a knot. Surgery on a slightly more special class of clovers preserves invertible concordance. We also show that the converse is false. Similar results hold for clovers with at least two loops vs. S -equivalence. AMS Classi cation 57N10; 57M25
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The m-clover is the plane curve defined by the polar equation rm/2 = cos (m2 θ). In this article we extend a well-known derivation of the Wallis product to derive a generalized Wallis product for arc lengths of m-clovers.
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1. INTRODUCTION. In 1826 Abel discovered that the lemniscate, the curve (x 2 + y 2) 2 = x 2 − y 2 pictured in Figure 1, can be divided into n arcs of equal length by straightedge and compass if and only if n is a power of 2 times a product of distinct Fermat primes [1, p. 314]. By an earlier theorem of Gauss, these are exactly the values of n for which a regular n-gon is constructible by straig...
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Clovers and other legumes are highly desirable species in pastures and hay meadows. First, legumes are able to obtain nitrogen from air through their symbiotic relationship with Rhizobium bacteria and, there fore, are not dependent on nitrogen fertilizer. The fixed nitrogen is primarily used to support clover growth, but parts of it become avail able to neighboring grass plants when clover ti...
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Two porphyrin-bridged tetranuclear platinum(II) complexes are found to effectively stabilize various kinds of G-quadruplexes. Their clover-like shape endows them with the capability of targeting G-quadruplexes rather than the double-stranded structure. Their excellent anticancer activity is the result of a dual effect, inhibition of the telomerase activity and repression of oncogene expression.
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ژورنال
عنوان ژورنال: Algebraic & Geometric Topology
سال: 2001
ISSN: 1472-2739,1472-2747
DOI: 10.2140/agt.2001.1.687