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A307465
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Number of Catalan words of length n avoiding the pattern 110.
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1
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1, 1, 2, 5, 13, 33, 82, 201, 489, 1185, 2866, 6925, 16725, 40385, 97506, 235409, 568337, 1372097, 3312546, 7997205, 19306973, 46611169, 112529330, 271669849, 655869049, 1583407969, 3822685010, 9228778013, 22280241061, 53789260161, 129858761410
(list;
graph;
refs;
listen;
history;
text;
internal format)
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OFFSET
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0,3
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LINKS
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FORMULA
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G.f.: (1-3*x+2*x^2+x^3)/((1-x)^2*(1-2*x-x^2)).
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MAPLE
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(1-3*x+2*x^2+x^3)/(1-x)^2/(1-2*x-x^2) ;
taylor(%, x=0, 30) ;
gfun[seriestolist](%) ;
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CROSSREFS
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KEYWORD
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nonn,easy
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AUTHOR
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STATUS
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approved
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