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A135353
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a(n) = 3*a(n-1) - 3*a(n-2) + 2*a(n-3).
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2
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2, -3, 3, 22, 51, 93, 170, 333, 675, 1366, 2739, 5469, 10922, 21837, 43683, 87382, 174771, 349533, 699050, 1398093, 2796195, 5592406, 11184819, 22369629, 44739242, 89478477, 178956963, 357913942, 715827891, 1431655773
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OFFSET
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0,1
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COMMENTS
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Sequence identical to its third differences. "Self-transform". Initial terms are transform's coefficients .
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LINKS
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FORMULA
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a(n) = (8/3)*2^n - (2/3)*cos(Pi*n/3) - (16*sqrt(3)/3)*sin(Pi*n/3). - Richard Choulet, Jan 02 2008
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MATHEMATICA
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LinearRecurrence[{3, -3, 2}, {2, -3, 3}, 30] (* or *) CoefficientList[Series[ (-2+9 x-18 x^2)/(-1+3 x-3 x^2+2 x^3), {x, 0, 30}], x] (* Harvey P. Dale, Apr 20 2011 *)
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CROSSREFS
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KEYWORD
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sign
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AUTHOR
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EXTENSIONS
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STATUS
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approved
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