Journal of Integer Sequences, Vol. 15 (2012), Article 12.6.2 |
Lara K. Pudwell
Department of Mathematics and Computer Science
Valparaiso University
Valparaiso, IN 46383
USA
Abstract:
In an earlier work, the authors studied pattern avoidance in colored set partitions in the equality sense. Here we study pattern avoidance in colored partitions in the pattern sense. We say that contains in the pattern sense if contains a copy when the colors are ignored and the colors on this copy of are order isomorphic to the colors on . Otherwise we say that avoids .
We focus on patterns from and find that many familiar and some new integer sequences appear. We provide bijective proofs wherever possible, and we provide formulas for computing those sequences that are new.
(Concerned with sequences
A000027
A000079
A000110
A000898
A000918
A001861
A005425
A005843
A011965
A014322
A052889
A052944
A081124.)
Received March 17 2012; revised version received June 9 2012. Published in Journal of Integer Sequences, June 13 2012.