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 A111662 Expansion of x^2*(1-x)*(x^2+x+1)*(x^6+x^3+1)/((2*x-1)*(2*x^9-x^6+x^3-1)). 3
 0, 0, 1, 2, 4, 9, 18, 36, 72, 144, 288, 576, 1152, 2304, 4610, 9220, 18440, 36882, 73764, 147528, 295056, 590112, 1180224, 2360450, 4720900, 9441800, 18883606, 37767212, 75534424, 151068852, 302137704, 604275408, 1208550818, 2417101636 (list; graph; refs; listen; history; text; internal format)
 OFFSET 0,4 COMMENTS Initial terms factored: [0,0,1,2,(2)^2,(3)^2,(2) (3)^2,(2)^2 (3)^2,(2)^3 (3)^2,(2)^4 (3)^2,(2)^5 (3)^2,(2)^6 (3)^2,(2)^7 (3)^2,(2)^8 (3)^2,(2) (5) (461),(2)^2 (5) (461),(2)^3 (5) (461),(2) (3)^3 (683),(2)^2 (3)^3 (683),(2)^3 (3)^3 (683),(2)^4 (3)^3 (683),(2)^5 (3)^3 (683),(2)^6 (3)^3 (683),(2) (5)^2 (17) (2777),(2)^2 (5)^2 (17) (2777),(2)^3 (5)^2 (17) (2777),(2) (7) (19) (70991),(2)^2 (7) (19) (70991),(2)^3 (7) (19) (70991),(2)^2 (3)^2 (11) (381487)] LINKS G. C. Greubel, Table of n, a(n) for n = 0..1000 MATHEMATICA CoefficientList[Series[x^2*(1 - x)*(x^2 + x + 1)*(x^6 + x^3 + 1)/((2*x - 1)*(2*x^9 - x^6 + x^3 - 1)), {x, 0, 50}], x] (* G. C. Greubel, Jun 09 2017 *) PROG Floretion Algebra Multiplication Program, FAMP Code: 2ibaseksumseq[.5'i + .5i' + .5'ii' + .5'jj' + .5'kk' + .5e], sumtype: sum[(Y[0], Y[1], Y[2]), mod(3) (PARI) Vec(x^2*(1-x)*(x^2+x+1)*(x^6+x^3+1)/((2*x-1)*(2*x^9-x^6+x^3-1))+O(x^99)) \\ Charles R Greathouse IV, Sep 26 2012 CROSSREFS Cf. A111663. Sequence in context: A138196 A101351 A293333 * A253585 A119027 A145139 Adjacent sequences:  A111659 A111660 A111661 * A111663 A111664 A111665 KEYWORD nonn,easy AUTHOR Creighton Dement, Aug 14 2005 STATUS approved

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