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A251418
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Floor((n^2+7n-23)/14).
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2
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-2, -2, -1, 0, 1, 2, 3, 5, 6, 8, 10, 12, 14, 16, 19, 21, 24, 27, 30, 33, 36, 40, 43, 47, 51, 55, 59, 63, 68, 72, 77, 82, 87, 92, 97, 103, 108, 114, 120, 126, 132, 138, 145, 151, 158, 165, 172, 179, 186, 194, 201, 209, 217, 225, 233, 241, 250, 258, 267, 276
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OFFSET
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0,1
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COMMENTS
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This is conjectured to be the value of the dominance number of the triangle grid graph for n >= 14 - see A251419.
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LINKS
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FORMULA
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G.f.: (3*x^8-3*x^7-x^2-2*x+2) / ((x-1)^3*(x^6+x^5+x^4+x^3+x^2+x+1)). - Colin Barker, Jul 10 2015
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MATHEMATICA
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LinearRecurrence[{2, -1, 0, 0, 0, 0, 1, -2, 1}, {-2, -2, -1, 0, 1, 2, 3, 5, 6}, 60] (* Harvey P. Dale, Mar 19 2020 *)
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PROG
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(PARI) Vec((3*x^8-3*x^7-x^2-2*x+2)/((x-1)^3*(x^6+x^5+x^4+x^3+x^2+x+1)) + O(x^100)) \\ Colin Barker, Jul 10 2015
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CROSSREFS
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KEYWORD
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sign,easy
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AUTHOR
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EXTENSIONS
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STATUS
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approved
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