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A289588
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Related to number of mesh patterns of length 2 that avoid the pattern 321.
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0
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1, 1, 1, 2, 4, 11, 34, 110, 365, 1234, 4237
(list;
graph;
refs;
listen;
history;
text;
internal format)
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OFFSET
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1,4
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LINKS
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FORMULA
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G.f.: (x^4+x^3-x^2)*C(x)/(x-1) - (x^4-x^2+x)/(x-1) where C(x) is the g.f. for the Catalan numbers (A000108) (conjectured). - Michael D. Weiner, Aug 08 2019
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CROSSREFS
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KEYWORD
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nonn,more
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AUTHOR
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STATUS
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approved
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