login
The OEIS is supported by the many generous donors to the OEIS Foundation.

 

Logo
Hints
(Greetings from The On-Line Encyclopedia of Integer Sequences!)
A080011 Number of permutations satisfying -k<=p(i)-i<=r and p(i)-i not in I, i=1..n, with k=2, r=3, I={-1}. 0

%I #17 Apr 16 2024 03:15:46

%S 1,1,1,3,7,15,29,59,126,262,542,1121,2328,4839,10039,20827,43220,

%T 89704,186172,386345,801768,1663916,3453137,7166272,14872078,30863935,

%U 64051787,132926308,275861116,572492846,1188091024,2465638247

%N Number of permutations satisfying -k<=p(i)-i<=r and p(i)-i not in I, i=1..n, with k=2, r=3, I={-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

%H <a href="/index/Rec#order_10">Index entries for linear recurrences with constant coefficients</a>, signature (1,1,1,2,3,-1,0,1,-1,-1).

%F a(n) = a(n-1)+a(n-2)+a(n-3)+2*a(n-4)+3*a(n-5)-a(n-6)+a(n-8)-a(n-9)-a(n-10).

%F G.f.: -(x^5+x^2-1)/(x^10+x^9-x^8+x^6-3*x^5-2*x^4-x^3-x^2-x+1)

%t LinearRecurrence[{1,1,1,2,3,-1,0,1,-1,-1},{1,1,1,3,7,15,29,59,126,262},40] (* _Harvey P. Dale_, Nov 03 2022 *)

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

%K nonn,changed

%O 0,4

%A _Vladimir Baltic_, Feb 10 2003

Lookup | Welcome | Wiki | Register | Music | Plot 2 | Demos | Index | Browse | More | WebCam
Contribute new seq. or comment | Format | Style Sheet | Transforms | Superseeker | Recents
The OEIS Community | Maintained by The OEIS Foundation Inc.

License Agreements, Terms of Use, Privacy Policy. .

Last modified April 19 18:58 EDT 2024. Contains 371798 sequences. (Running on oeis4.)