OFFSET
0,3
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 (1, 3, -1, 1, 1, 3, -5, -9, 1, 1, 1, -1, 1, 1).
FORMULA
a(n) = a(n-1) +3*a(n-2) -a(n-3) +a(n-4) +a(n-5) +3*a(n-6) -5*a(n-7) -9*a(n-8) +a(n-9) +a(n-10) +a(n-11) -a(n-12) +a(n-13) +a(n-14).
G.f.: -(x^2-1)*(x^6+x^4+x^3+x^2-1)/(x^14 +x^13 -x^12 +x^11 +x^10 +x^9 -9*x^8 -5*x^7 +3*x^6 +x^5 +x^4 -x^3 +3*x^2 +x-1)
CROSSREFS
KEYWORD
nonn,easy
AUTHOR
Vladimir Baltic, Feb 17 2003
STATUS
approved