Denumerations of rooted trees and multisets
نویسندگان
چکیده
منابع مشابه
Denumerations of rooted trees and multisets
R\I stands for the set of positive integers, and li$, for the set of non-negative integers. If S is a set then IS( is the number of elements of S. If S is a set, then a multiset of elements of S is a mapping f of S into &, with the property that the set of s with f(s)>0 is finite. The set of all these multisets is denoted M(S). Some of our multisets are multisets of natural numbers. Number theo...
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ژورنال
عنوان ژورنال: Discrete Applied Mathematics
سال: 1983
ISSN: 0166-218X
DOI: 10.1016/0166-218x(83)90097-5