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A079975 Number of permutations satisfying -k<=p(i)-i<=r and p(i)-i not in I, i=1..n, with k=1, r=4, I={3}. 0

%I

%S 1,1,2,4,7,14,26,49,93,175,331,625,1180,2229,4209,7949,15012,28350,

%T 53540,101111,190950,360613,681024,1286127,2428875,4586976,8662591,

%U 16359466,30895160,58346092,110187694,208091537,392984789,742159180

%N Number of permutations satisfying -k<=p(i)-i<=r and p(i)-i not in I, i=1..n, with k=1, r=4, I={3}.

%C Number of compositions (ordered partitions) of n into elements of the set {1,2,3,5}.

%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">Index entries for linear recurrences with constant coefficients</a>, signature (1,1,1,0,1).

%F Recurrence: a(n) = a(n-1)+a(n-2)+a(n-3)+a(n-5).

%F G.f.: -1/(x^5+x^3+x^2+x-1)

%Y Cf. A002524-A002529, A072827, A072850-A072856, A079955-A080014.

%K nonn

%O 0,3

%A _Vladimir Baltic_, Feb 17 2003

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Last modified June 4 05:19 EDT 2020. Contains 334815 sequences. (Running on oeis4.)