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A079973
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Number of permutations satisfying -k<=p(i)-i<=r and p(i)-i not in I, i=1..n, with k=1, r=4, I={0,3}.
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3
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1, 0, 1, 1, 1, 3, 2, 5, 6, 8, 14, 16, 27, 36, 51, 77, 103, 155, 216, 309, 448, 628, 912, 1292, 1849, 2652, 3769, 5413, 7713, 11031, 15778, 22513, 32222, 46004, 65766, 94004, 134283, 191992, 274291, 392041, 560287, 800615, 1144320, 1635193, 2336976
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OFFSET
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0,6
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COMMENTS
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Number of compositions (ordered partitions) of n into elements of the set {2,3,5}.
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REFERENCES
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D. H. Lehmer, Permutations with strongly restricted displacements. Combinatorial theory and its applications, II (Proc. Colloq., Balatonfured, 1969), pp. 755-770. North-Holland, Amsterdam, 1970.
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LINKS
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Table of n, a(n) for n=0..44.
Vladimir Baltic, On the number of certain types of strongly restricted permutations, Applicable Analysis and Discrete Mathematics Vol. 4, No 1 (2010), 119-135
Index to sequences with linear recurrences with constant coefficients, signature (0,1,1,0,1).
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FORMULA
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a(n) = a(n-2)+a(n-3)+a(n-5).
G.f.: -1/(x^5+x^3+x^2-1)
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CROSSREFS
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Row sums of A059484. - N. J. A. Sloane, Jun 02 2009
Cf. A002524-A002529, A072827, A072850-A072856, A079955-A080014.
Sequence in context: A175058 A154437 A083236 * A055922 A194072 A194105
Adjacent sequences: A079970 A079971 A079972 * A079974 A079975 A079976
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KEYWORD
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nonn
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AUTHOR
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Vladimir Baltic, Feb 17 2003
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STATUS
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approved
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