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%I #17 Apr 16 2024 04:17:21
%S 1,0,1,0,2,1,4,2,7,5,14,12,27,26,53,57,106,122,212,258,428,543,868,
%T 1135,1766,2364,3605,4910,7374,10175,15109,21054,30998,43513,63656,
%U 89851,130817,185416,268984,382436,553308,788520,1138525,1625356,2343253
%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={0,2}.
%C Number of compositions (ordered partitions) of n into elements of the set {2,4,5,6}.
%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 (0,1,0,1,1,1).
%F a(n) = a(n-2)+a(n-4)+a(n-5)+a(n-6).
%F G.f.: -1/(x^6+x^5+x^4+x^2-1).
%Y Cf. A002524-A002529, A072827, A072850-A072856, A079955-A080014.
%K nonn,easy
%O 0,5
%A _Vladimir Baltic_, Feb 19 2003
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