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 A077988 Expansion of 1/(1+2*x-2*x^3). 3
 1, -2, 4, -6, 8, -8, 4, 8, -32, 72, -128, 192, -240, 224, -64, -352, 1152, -2432, 4160, -6016, 7168, -6016, 0, 14336, -40704, 81408, -134144, 186880, -210944, 153600, 66560, -555008, 1417216, -2701312, 4292608, -5750784, 6098944, -3612672, -4276224, 20750336, -48726016, 88899584 (list; graph; refs; listen; history; text; internal format)
 OFFSET 0,2 LINKS G. C. Greubel, Table of n, a(n) for n = 0..1000 J. Pan, Multiple Binomial Transforms and Families of Integer Sequences , J. Int. Seq. 13 (2010), 10.4.2, T^(-1). Index entries for linear recurrences with constant coefficients, signature (-2, 0, 2). FORMULA a(n) = (-1)^n * A077940(n). - G. C. Greubel, Jun 25 2019 MATHEMATICA LinearRecurrence[{-2, 0, 2}, {1, -2, 4}, 50] (* Vladimir Joseph Stephan Orlovsky, May 25 2011 *) CoefficientList[Series[1/(1+2x-2x^3), {x, 0, 50}], x] (* Harvey P. Dale, May 21 2024 *) PROG (PARI) my(x='x+O('x^50)); Vec(1/(1+2*x-2*x^3)) \\ G. C. Greubel, Jun 25 2019 (Magma) R:=PowerSeriesRing(Integers(), 50); Coefficients(R!( 1/(1+2*x-2*x^3) )); // G. C. Greubel, Jun 25 2019 (Sage) (1/(1+2*x-2*x^3)).series(x, 50).coefficients(x, sparse=False) # G. C. Greubel, Jun 25 2019 (GAP) a:=[1, -2, 4];; for n in [4..50] do a[n]:=-2*a[n-1]+2*a[n-3]; od; a; # G. C. Greubel, Jun 25 2019 CROSSREFS Cf. A000073, A001590, A000213, A077940, A135491. Sequence in context: A237047 A021806 A077940 * A166880 A079088 A161661 Adjacent sequences: A077985 A077986 A077987 * A077989 A077990 A077991 KEYWORD sign,easy AUTHOR N. J. A. Sloane, Nov 17 2002 STATUS approved

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Last modified September 17 03:10 EDT 2024. Contains 375984 sequences. (Running on oeis4.)