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تسجيل مستخدم جديدEnumeration of $(k,2)$-noncrossing partitions
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A set partition is said to be $(k,d)$-noncrossing if it avoids the pattern $12... k12... d$. We find an explicit formula for the ordinary generating function of the number of $(k,d)$-noncrossing partitions of ${1,2,...,n}$ when $d=1,2$.
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