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A079980 Number of permutations of length 2n satisfying -k<=p(i)-i<=r and p(i)-i not in I, i=1..2n, with k=3, r=3, I={-2,0,1,2}. There is no one such permutation of length 2n+1. 1

%I #16 Apr 16 2024 10:34:44

%S 1,0,1,2,3,8,12,27,52,95,196,369,720,1408,2709,5292,10249,19894,38675,

%T 74992,145692,282823,549000,1066095,2069496,4018065,7801024,15144960,

%U 29404281,57086680,110832225,215178138,417759539,811069560,1574664364

%N Number of permutations of length 2n satisfying -k<=p(i)-i<=r and p(i)-i not in I, i=1..2n, with k=3, r=3, I={-2,0,1,2}. There is no one such permutation of length 2n+1.

%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_09">Index entries for linear recurrences with constant coefficients</a>, signature (0,1,4,2,2,-2,1,0,1).

%F Recurrence: a(n) = a(n-2)+4*a(n-3)+2*a(n-4)+2*a(n-5)-2*a(n-6)+a(n-7)+a(n-9).

%F G.f.: -(x^6-2*x^3+1)/(x^9+x^7-2*x^6+2*x^5+2*x^4+4*x^3+x^2-1).

%Y Subsequence of A079981.

%K nonn,easy,changed

%O 0,4

%A _Vladimir Baltic_, Feb 17 2003

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Last modified April 25 05:49 EDT 2024. Contains 371964 sequences. (Running on oeis4.)