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A256335
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Number of Largest Chain Family matchings on n edges.
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0
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1, 3, 15, 93, 639, 4670, 35607, 280069, 2255979, 18516875, 154313881, 1302252294, 11106135906, 95571461319, 828803505465, 7235996887013, 63549647848195, 561049960940540, 4976419846070007, 44325237810194705, 396301576614077927, 3555397444230816343, 31996727212476905751, 288776859922595203094, 2613107152879937592054, 23702850369539462227046, 215483061767106353850246, 1963017891713523908516093, 17917224620763719834090179, 163830901587493323034301583, 1500542646711279198177939831, 13765184019931774406496702885
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OFFSET
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1,2
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COMMENTS
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The Largest Chain Family of matchings is the largest family of matchings formed by repeated edge inflations and vertex insertions into any length n chain.
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LINKS
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FORMULA
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G.f. f satisfies x^3f^6+x^2f^5-4x^2f^4+2xf^3+(x+4)f^2-11f+7 = 0.
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EXAMPLE
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a(4)=93 because of the 105 matchings on 4 edges, there are 13 matchings which do not lie in the Largest Chain Family. Two such matching in canonical sequence form, are given by 12343142 and 12342413.
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MAPLE
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f := RootOf(_Z^6*x^3+_Z^5*x^2-4*_Z^4*x^2+2*_Z^3*x+_Z^2*x+4*_Z^2-11*_Z+7, 1);
series(f, x=0, 30);
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CROSSREFS
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KEYWORD
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nonn
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AUTHOR
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STATUS
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approved
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