This is a front-end for the Online Encyclopedia of Integer Sequences, made by Christian Perfect. The idea is to provide OEIS entries in non-ancient HTML, and then to think about how they're presented visually. The source code is on GitHub.
%I A080003 #15 Apr 16 2024 03:21:19
%S A080003 1,1,1,1,4,8,13,22,40,77,140,252,456,834,1525,2775,5049,9195,16760,
%T A080003 30536,55617,101304,184544,336193,612424,1115600,2032216,3702000,
%U A080003 6743761,12284729,22378393,40765513,74260396,135276192,246425309
%N A080003 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={1,2}.
%D A080003 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 A080003 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 A080003 <a href="/index/Rec#order_10">Index entries for linear recurrences with constant coefficients</a>, signature (1,0,1,2,2,0,1,-1,0,-1).
%F A080003 Recurrence: a(n) = a(n-1)+a(n-3)+2*a(n-4)+2*a(n-5)+a(n-7)-a(n-8)-a(n-10).
%F A080003 G.f.: -(x^5+x^3-1)/(x^10+x^8-x^7-2*x^5-2*x^4-x^3-x+1)
%Y A080003 Cf. A002524-A002529, A072827, A072850-A072856, A079955-A080014.
%K A080003 nonn
%O A080003 0,5
%A A080003 _Vladimir Baltic_, Feb 10 2003