OFFSET
0,5
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 (0,1,2,2,4,0,-2,-1,0,-1).
FORMULA
a(n) = a(n-2)+2*a(n-3)+2*a(n-4)+4*a(n-5)-2*a(n-7)-a(n-8)-a(n-10).
G.f.: -(x^5+x^3+x^2-1)/(x^10+x^8+2*x^7-4*x^5-2*x^4-2*x^3-x^2+1)
CROSSREFS
KEYWORD
nonn
AUTHOR
Vladimir Baltic, Feb 10 2003
STATUS
approved