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%I #15 Apr 16 2024 04:14:32
%S 1,1,2,3,6,10,19,33,60,106,191,340,610,1089,1950,3485,6236,11150,
%T 19946,35670,63802,114107,204091,365018,652857,1167652,2088402,
%U 3735179,6680529,11948378,21370166,38221375,68360472,122265404,218676571
%N 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={2,4}.
%C Number of compositions (ordered partitions) of n into elements of the set {1,2,4,6}.
%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.
%H <a href="/index/Rec#order_06">Index entries for linear recurrences with constant coefficients</a>, signature (1,1,0,1,0,1).
%F a(n) = a(n-1)+a(n-2)+a(n-4)+a(n-6).
%F G.f.: -1/(x^6+x^4+x^2+x-1).
%Y Cf. A002524-A002529, A072827, A072850-A072856, A079955-A080014.
%K nonn,easy
%O 0,3
%A _Vladimir Baltic_, Feb 19 2003
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