On Sequences G n Satisfying G n = ( d + 2 ) G n − 1 − G n − 2 Ricky X . F . Chen Center for Combinatorics LPMC
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چکیده
In this note, we study a class of sequences Gn satisfying Gn = (d+2)Gn−1 −Gn−2. Note that the Fibonacci numbers Gn = F2n, n > 1 and Gn = F2n+1, n > 0 occur when d = 1 with suitable initial conditions. We present a general interpretation for this class of sequences in terms of ordered trees which we count by nodes and outdegrees. Further more, several other related integer sequences are also studied.
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تاریخ انتشار 2007