Pattern avoidance in “flattened” partitions
نویسندگان
چکیده
منابع مشابه
Pattern avoidance in "flattened" partitions
To atten a set partition (with apologies to Mathematica r ) means to form a permutation by erasing the dividers between its blocks. Of course, the result depends on how the blocks are listed. For the usual listing|increasing entries in each block and blocks arranged in increasing order of their rst entries|we count the partitions of [n] whose attening avoids a single 3-letter pattern. Five coun...
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ژورنال
عنوان ژورنال: Discrete Mathematics
سال: 2009
ISSN: 0012-365X
DOI: 10.1016/j.disc.2008.11.019