OFFSET
0,5
COMMENTS
Number of compositions (ordered partitions) of n into elements of the set {2,4,5,6}.
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.
Index entries for linear recurrences with constant coefficients, signature (0,1,0,1,1,1).
FORMULA
a(n) = a(n-2)+a(n-4)+a(n-5)+a(n-6).
G.f.: -1/(x^6+x^5+x^4+x^2-1).
CROSSREFS
KEYWORD
nonn,easy
AUTHOR
Vladimir Baltic, Feb 19 2003
STATUS
approved