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A052943
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Expansion of (1-x^2)/(1-2x^2-x^3+x^5).
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0
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1, 0, 1, 1, 2, 2, 5, 5, 11, 13, 25, 32, 58, 78, 135, 189, 316, 455, 743, 1091, 1752, 2609, 4140, 6227, 9798, 14842, 23214, 35342, 55043, 84100, 130586, 200029, 309930, 475601, 735789, 1130546, 1747150, 2686951, 4149245, 6385263, 9854895
(list; graph; refs; listen; history; internal format)
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OFFSET
| 0,5
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LINKS
| INRIA Algorithms Project, Encyclopedia of Combinatorial Structures 934
Index to sequences with linear recurrences with constant coefficients, signature (0,2,1,0,-1).
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FORMULA
| G.f.: -(-1+x^2)/(1-2*x^2-x^3+x^5)
Recurrence: {a(1)=0, a(0)=1, a(2)=1, a(3)=1, a(4)=2, a(n)-a(n+2)-2*a(n+3)+a(n+5)=0}
Sum(-1/4511*(-330+224*_alpha^2-1089*_alpha+100*_alpha^4+167*_alpha^3)*_alpha^(-1-n), _alpha=RootOf(1-2*_Z^2-_Z^3+_Z^5))
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MAPLE
| spec := [S, {S=Sequence(Prod(Z, Z, Union(Z, Sequence(Prod(Z, Z)))))}, unlabeled ]: seq(combstruct[count ](spec, size=n), n=0..20);
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CROSSREFS
| Sequence in context: A184321 A103891 A005294 * A184307 A032580 A002014
Adjacent sequences: A052940 A052941 A052942 * A052944 A052945 A052946
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KEYWORD
| easy,nonn
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AUTHOR
| encyclopedia(AT)pommard.inria.fr, Jan 25 2000
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EXTENSIONS
| More terms from James A. Sellers (sellersj(AT)math.psu.edu), Jun 05 2000
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