Table 1. Sequences enumerating the (1,2) avoidance classes for Catalan words τ Sequence Reference 1-11 1,1,1,3,6,15,39,102,275,754 Theorem 5.15 1-12 A000045 in [11] Observation 6.2 1-21 1,1,1,1,1,1,1,1,1,1 Observation 6.1 1-22 A001006 Theorem 3.3 1-23 1,1,2,5,13,33,82,202,497,1224 Proposition 2.2 and Theorem 5.4 1-32 A000325 Observation 6.2 2-11 1,1,2,4,10,26,71,199,570,1659 Open 2-12 1,1,2,4,9,22,56,146,388,1047 Proposition 2.2 and Theorem 4.3 2-13 1,1,2,5,13,34,91,248,685,1911 Proposition 2.2 and Theorem 5.8 2-21 A011782 Observation 6.2 2-31 A000108 Observation 6.1 3-12 1,1,2,5,14,41,123,376,1167,3665 Proposition 2.2 and Theorem 4.5 3-21 A001519 Observation 6.2 Toufik Mansour et al. Avoidance of Type (1,2) Patterns by Catalan Words. Turkish Journal of Analysis and Number Theory, 2017, Vol. 5, No. 3, 101-116. doi:10.12691/tjant-5-3-4 © The Author(s) 2015. Published by Science and Education Publishing.
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