The number of caterpillars
نویسندگان
چکیده
A caterpillar is a tree which metamorphoses into a path when its cocoon of endpoInt\ is removed. The number of nonisomorphic caterpillars with n + 4 points is 2n + 2 [n/21 . This neat formula is proved in two ways: first, as a special caoe of an application of Pblya’s enumerration theorem which counts graphs with integer-weightell points; secondly, 3y an appropriate labeling of the lines of the caterpillar.
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ورودعنوان ژورنال:
- Discrete Mathematics
دوره 6 شماره
صفحات -
تاریخ انتشار 1973