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A138849
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a(n) = AlexanderPolynomial[n] defined as Det[Transpose[S]-n S] where S is Kronecker Product of two 2 X 2 Seifert matrices {{-1, 1}, {0, -1}} [X] {{-1, 1}, {0, -1}} = {{1, -1, -1, 1}, {0, 1, 0, -1}, {0, 0, 1, -1}, {0, 0, 0, 1}}.
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2
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1, 0, 7, 52, 189, 496, 1075, 2052, 3577, 5824, 8991, 13300, 18997, 26352, 35659, 47236, 61425, 78592, 99127, 123444, 151981, 185200, 223587, 267652, 317929, 374976, 439375, 511732, 592677, 682864, 782971, 893700, 1015777, 1149952, 1296999, 1457716, 1632925
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OFFSET
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1,3
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LINKS
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FORMULA
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a(n) = Det[Transpose[}}={{1, -1, -1, 1}, {0, 1, 0, -1}, {0, 0, 1, -1}, {0, 0, 0, 1}}] - n {{1, -1, -1, 1}, {0, 1, 0, -1}, {0, 0, 1, -1}, {0, 0, 0, 1}}].
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MAPLE
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MATHEMATICA
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S = {{1, -1, -1, 1}, {0, 1, 0, -1}, {0, 0, 1, -1}, {0, 0, 0, 1}}; Table[Det[Transpose[S] - n S], {n, 0, 30}] (* Artur Jasinski *)
CoefficientList[Series[(1 - 5 x + 17 x^2 + 7 x^3 + 4 x^4)/(1 - x)^5, {x, 0, 40}], x] (* Vincenzo Librandi, Nov 22 2015 *)
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PROG
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(PARI) vector(40, n, n^4-5*n^3+9*n^2-8*n+4) \\ Altug Alkan, Nov 22 2015
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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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EXTENSIONS
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STATUS
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approved
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