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A052989
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Expansion of ( 1-x ) / ( 1-x-x^2-x^4+x^5 ).
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0
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1, 0, 1, 1, 3, 3, 7, 10, 19, 29, 52, 84, 145, 239, 407, 678, 1146, 1918, 3232, 5421, 9121, 15314, 25749, 43252, 72701, 122146, 205282, 344931, 579662, 974038, 1636836, 2750523, 4622090, 7766989, 13051877, 21932553, 36855997, 61933449, 104074334
(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 1063
Index to sequences with linear recurrences with constant coefficients, signature (1,1,0,1,-1).
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FORMULA
| G.f.: -(-1+x)/(1-x-x^2-x^4+x^5)
Recurrence: {a(1)=0, a(0)=1, a(2)=1, a(3)=1, a(4)=3, a(n)-a(n+1)-a(n+3)-a(n+4)+a(n+5) =0}
Sum(-1/8519*(-389-2111*_alpha+619*_alpha^2-358*_alpha^3+541*_alpha^4)*_alpha^(-1-n), _alpha=RootOf(1-_Z-_Z^2-_Z^4+_Z^5))
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MAPLE
| spec := [S, {S=Sequence(Prod(Union(Prod(Z, Z), Sequence(Z)), Z, Z))}, unlabeled ]: seq(combstruct[count ](spec, size=n), n=0..20);
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CROSSREFS
| Sequence in context: A157933 A013915 A136445 * A022403 A082550 A036056
Adjacent sequences: A052986 A052987 A052988 * A052990 A052991 A052992
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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 06 2000
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