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A107458
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Expansion of g.f.: (1-x^2-x^3)/( (1+x)*(1-x-x^3) ).
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5
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1, 0, 0, 0, 1, 0, 1, 1, 2, 2, 4, 5, 8, 11, 17, 24, 36, 52, 77, 112, 165, 241, 354, 518, 760, 1113, 1632, 2391, 3505, 5136, 7528, 11032, 16169, 23696, 34729, 50897, 74594, 109322, 160220, 234813, 344136, 504355, 739169, 1083304, 1587660, 2326828, 3410133, 4997792, 7324621
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OFFSET
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0,9
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COMMENTS
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The sequence can be interpreted as the top-left entry of the n-th power of a 4 X 4 (0,1) matrix. There are 12 different choices (out of 2^16) for that (0,1) matrix. - R. J. Mathar, Mar 19 2014
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LINKS
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Renata Passos Machado Vieira, Francisco Regis Vieira Alves, Sequences of Tridovan and their identities, Notes on Number Theory and Discrete Mathematics (2019) Vol. 25, No. 3, 185-197. Sequence (T_n) is a subsequence of this sequence.
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FORMULA
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a(n) = a(n-2) + a(n-3) + a(n-4); a(0)=1, a(1)=0, a(2)=0, a(3)=0. - Harvey P. Dale, Jun 20 2011
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MAPLE
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seq(coeff(series( (1-x^2-x^3)/( (1+x)*(1-x-x^3) ), x, n+1), x, n), n = 0..50); # G. C. Greubel, Jan 03 2020
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MATHEMATICA
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CoefficientList[Series[(1-x^2-x^3)/(1-x^2-x^3-x^4), {x, 0, 50}], x] (* or *) LinearRecurrence[{0, 1, 1, 1}, {1, 0, 0, 0}, 50] (* Harvey P. Dale, Jun 20 2011 *)
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PROG
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(Haskell)
a107458 n = a107458_list !! n
a107458_list = 1 : 0 : 0 : 0 : zipWith (+) a107458_list
(zipWith (+) (tail a107458_list) (drop 2 a107458_list))
(PARI) my(x='x+O('x^50)); Vec((1-x^2-x^3)/((1+x)*(1-x-x^3))) \\ G. C. Greubel, Apr 27 2017
(Magma) R<x>:=PowerSeriesRing(Integers(), 50); Coefficients(R!(1-x^2-x^3)/( (1+x)*(1-x-x^3))); // Marius A. Burtea, Jan 02 2020
(Sage)
P.<x> = PowerSeriesRing(ZZ, prec)
return P( (1-x^2-x^3)/((1+x)*(1-x-x^3)) ).list()
(GAP) a:=[1, 0, 0, 0];; for n in [5..50] do a[n]:=a[n-2]+a[n-3]+a[n-4]; od; a; # G. C. Greubel, Jan 03 2020
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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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