On a formula for the number of Euler trails for a class of digraphs
نویسنده
چکیده
In this note we give an elementary combinatorial proof of a formula of Macris and Pul6 for the number of Euler trails in a digraph all of whose vertices have in-degree and out-degree equal to2.
منابع مشابه
On a determinant formula for enumerating Euler trails in a class of digraphs
In 1996 Macris and Pulé [6] obtained a new determinant formula for the number of Euler trails in a special class of digraphs. An elementary combinatorial proof of this result was given in [5]. In this note we shall discuss possible extensions and generalisations of this result. Many of these observations are, as yet, in a very inconclusive state and they are being put forward here in the spirit...
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عنوان ژورنال:
- Discrete Mathematics
دوره 163 شماره
صفحات -
تاریخ انتشار 1997