Positive symmetric functions
نویسندگان
چکیده
منابع مشابه
Spectra with Positive Elementary Symmetric Functions
It is well known that if all the elementary symmetric functions of the eigenvalues of an n–by–n matrix are positive, then all its eigenvalues lie in the region of the complex plane {z : −π + πn < argz < π − π n}. Let A denote an n–by–n matrix with all diagonal entries nonzero and for which the length of the longest cycle in its directed graph is k, 2 ≤ k ≤ n. If, in addition, all the cycles in ...
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Lazard's theorem is a central result in formal group theory; it states that the ring over which the universal formal group law is deened (known as the Lazard ring) is a polynomial algebra over the integers with innnitely many generators. This ring also shows up in algebraic topology as the complex cobordism ring. The main aim of this paper is to show that the polynomial structure of the Lazard ...
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We show that the set of all functions is equivalent to the set of all symmetric functions up to deterministic time complexity. In particular, for any function f , there is an equivalent symmetric function fsym such that f can be computed form fsym and vice-versa (modulo an extra deterministic linear time computation). For f over finite fields, fsym is (necessarily) over an extension field. This...
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ژورنال
عنوان ژورنال: Advances in Mathematics
سال: 1978
ISSN: 0001-8708
DOI: 10.1016/0001-8708(78)90011-7