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%I #7 Jan 03 2019 05:26:38
%S 1,2,6,14,31,73,160,357,814,1836,4140,9379,21163,47769,107940,243763,
%T 550469,1243468,2808345,6342601,14325494,32354798,73074320,165043749,
%U 372759852,841897006,1901473298,4294581633,9699541870,21906956858
%N Number of length n arrays of permutations of 0..n-1 with each element moved by -2 to 2 places and every three consecutive elements having its maximum within 5 of its minimum.
%H R. H. Hardin, <a href="/A263746/b263746.txt">Table of n, a(n) for n = 1..210</a>
%F Empirical: a(n) = a(n-1) + 2*a(n-2) + 2*a(n-3) - 3*a(n-5) + 7*a(n-6) - a(n-7) - 2*a(n-8) - 5*a(n-9) - 3*a(n-10) + 2*a(n-11) + 2*a(n-13).
%F Empirical g.f.: x*(1 + x + 2*x^2 + 2*x^3 + x^4 + 5*x^5 - 4*x^6 - 6*x^7 - 5*x^8 - 2*x^9 + 3*x^10 + x^11 + 2*x^12) / (1 - x - 2*x^2 - 2*x^3 + 3*x^5 - 7*x^6 + x^7 + 2*x^8 + 5*x^9 + 3*x^10 - 2*x^11 - 2*x^13). - _Colin Barker_, Jan 03 2019
%e Some solutions for n=10:
%e ..0....0....0....1....1....0....1....1....0....2....0....0....2....1....0....0
%e ..1....2....2....0....0....1....0....2....3....0....3....1....3....0....2....1
%e ..3....1....3....3....2....3....3....0....1....4....1....2....0....3....1....4
%e ..2....3....1....4....3....2....2....5....4....1....2....3....1....2....4....5
%e ..6....4....5....2....4....4....5....4....2....5....6....5....4....6....3....2
%e ..5....6....6....6....5....6....6....3....7....3....7....4....6....5....5....3
%e ..4....5....4....7....6....8....4....8....6....8....4....7....5....4....6....6
%e ..9....7....7....5....7....5....8....7....5....6....5....8....8....8....8....7
%e ..7....9....9....9....8....9....7....6....9....9....8....6....7....7....9....8
%e ..8....8....8....8....9....7....9....9....8....7....9....9....9....9....7....9
%Y Column 2 of A263752.
%K nonn
%O 1,2
%A _R. H. Hardin_, Oct 25 2015
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