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A004057
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Expansion of (1-x)/( (1+x)*(1-2*x)*(1-3*x)*(1-4*x)).
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2
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1, 7, 39, 191, 875, 3843, 16423, 68887, 285219, 1170059, 4768127, 19336863, 78141883, 314953555, 1266977751, 5089412519, 20422176467, 81882328731, 328110270895, 1314184126255, 5261965982571, 21063553061987
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OFFSET
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0,2
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LINKS
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FORMULA
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a(n) = (1/30)*(20*2^n - 135*3^n + 144*4^n + (-1)^n).
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MATHEMATICA
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CoefficientList[Series[(1-x)/((1+x)(1-2x)(1-3x)(1-4x)), {x, 0, 30}], x] (* or *) LinearRecurrence[{8, -17, -2, 24}, {1, 7, 39, 191}, 30] (* Harvey P. Dale, Oct 22 2019 *)
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PROG
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(Magma) [(1/30)* (20*2^n - 135*3^n + 144*4^n + (-1)^n): n in [0..30]]; // Vincenzo Librandi, Oct 08 2011
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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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