A combinatorial interpretation of the recurrence fn+1 = 6fn - fn-1
نویسندگان
چکیده
Bonin et al. (1993) recalled an open problem related to the recurrence relation verified by NSW numbers. The recurrence relation is the following: fn+l = 6f~ f~l , with jq = 1 and j~ = 7, and no combinatorial interpretation seems to be known. In this note, we define a regular language .~ whose number of words having length n is equal to f~+l. Then, by using .La we give a direct combinatorial proof of the recurrence. (~) 1998 Elsevier Science B.V. All rights reserved
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ورودعنوان ژورنال:
- Discrete Mathematics
دوره 190 شماره
صفحات -
تاریخ انتشار 1998