On a 1-1-correspondence between rooted trees and natural numbers
نویسنده
چکیده
In the sequel, we suppose that p(l) = 2, p(2), p(3),... is the sequence of primes in ascending order. Let T be a rooted tree, r its root. The connected components of Tr are denoted by T, ,..., T,, where v is the degree of r. The graphs Tj ul,..., v) obviously are trees, which we transform into rooted trees by defining as the root of Tj the vertex of 7” which is adjacent to r in T. We now assign a natural number 4(T) to the rooted tree T.
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عنوان ژورنال:
- J. Comb. Theory, Ser. B
دوره 29 شماره
صفحات -
تاریخ انتشار 1980