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%I #9 Mar 31 2012 14:40:10
%S 1,0,0,0,1,2,4,0,4,10,29,40,64,88,221,420,800,1280,2336,4260,8325,
%T 15000,27200,48360,89541,164430,303300,549120,1001156,1824342,3350169,
%U 6122640,11189504,20391280,37266329,68097480,124548224,227452928,415474816
%N Number of permutations satisfying -k<=p(i)-i<=r and p(i)-i not in I, i=1..n, with k=3, r=3, I={-1,0,1}.
%D 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.
%H Vladimir Baltic, <a href="http://pefmath.etf.rs/vol4num1/AADM-Vol4-No1-119-135.pdf">On the number of certain types of strongly restricted permutations</a>, Applicable Analysis and Discrete Mathematics Vol. 4, No 1 (2010), 119-135
%F a(n) = a(n-1) +a(n-2) -a(n-3) +3*a(n-4) +2*a(n-5) +2*a(n-6) -6*a(n-7) -2*a(n-8) +2*a(n-9) -3*a(n-10) -a(n-11) -a(n-12) +a(n-13) +a(n-14)
%F G.f.: -(x^8+x^7-x^6-x^5-2*x^4+x^3-x^2-x+1)/(x^14 +x^13 -x^12 -x^11 -3*x^10 +2*x^9 -2*x^8 -6*x^7 +2*x^6 +2*x^5 +3*x^4 -x^3 +x^2 +x-1)
%Y Cf. A002524-A002529, A072827, A072850-A072856, A079955-A080014.
%K nonn
%O 0,6
%A _Vladimir Baltic_, Feb 17 2003
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