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A079956 Number of permutations satisfying -k<=p(i)-i<=r and p(i)-i not in I, i=1..n, with k=1, r=5, I={0,1,4}. 2
1, 0, 0, 1, 1, 0, 2, 2, 1, 3, 5, 3, 6, 10, 9, 12, 21, 22, 27, 43, 52, 61, 91, 117, 140, 195, 260, 318, 426, 572, 718, 939, 1258, 1608, 2083, 2769, 3584, 4630, 6110, 7961, 10297, 13509, 17655, 22888, 29916, 39125, 50840, 66313, 86696, 112853, 147069, 192134 (list; graph; refs; listen; history; text; internal format)
OFFSET
0,7
COMMENTS
Number of compositions (ordered partitions) of n into elements of the set {3,4,6}.
REFERENCES
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.
LINKS
Vladimir Baltic, On the number of certain types of strongly restricted permutations, Applicable Analysis and Discrete Mathematics Vol. 4, No 1 (2010), 119-135
FORMULA
a(n) = a(n-3)+a(n-4)+a(n-6) G.f.: -1/(x^6+x^4+x^3-1)
MATHEMATICA
LinearRecurrence[{0, 0, 1, 1, 0, 1}, {1, 0, 0, 1, 1, 0}, 60] (* Harvey P. Dale, Oct 05 2016 *)
CROSSREFS
Sequence in context: A054336 A342908 A284644 * A140717 A257005 A160232
KEYWORD
nonn
AUTHOR
Vladimir Baltic, Feb 19 2003
STATUS
approved

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Last modified March 18 21:02 EDT 2024. Contains 370951 sequences. (Running on oeis4.)