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A263691 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 3 of its minimum.

%I A263691 #11 Jan 02 2019 23:12:07
%S A263691 1,2,6,14,14,16,22,36,56,85,125,189,285,434,655,993,1499,2271,3432,
%T A263691 5197,7857,11893,17985,27218,41167,62293,94227,142571,215672,326309,
%U A263691 493637,746845,1129845,1709362,2585999,3912361,5918843,8954567,13547048
%N A263691 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 3 of its minimum.
%H A263691 R. H. Hardin, <a href="/A263691/b263691.txt">Table of n, a(n) for n = 1..210</a>
%F A263691 Empirical: a(n) = a(n-1) + a(n-2) - a(n-3) + a(n-4) for n>12.
%F A263691 Empirical g.f.: x*(1 + x + 3*x^2 + 7*x^3 - 5*x^4 - 8*x^5 - 2*x^7 - x^9 - 2*x^10 - x^11) / (1 - x - x^2 + x^3 - x^4). - _Colin Barker_, Jan 02 2019
%e A263691 Some solutions for n=7:
%e A263691 ..0....0....0....1....0....1....1....0....0....0....0....1....2....0....0....0
%e A263691 ..1....1....2....0....2....0....0....3....1....1....1....0....0....1....2....1
%e A263691 ..2....2....1....2....1....3....2....1....2....2....3....2....1....2....1....3
%e A263691 ..3....4....3....3....4....2....3....2....4....3....2....3....3....3....4....2
%e A263691 ..5....3....4....4....3....5....5....4....3....4....4....4....4....4....3....5
%e A263691 ..4....5....6....5....6....4....6....5....6....5....5....6....5....6....5....4
%e A263691 ..6....6....5....6....5....6....4....6....5....6....6....5....6....5....6....6
%Y A263691 Column 2 of A263693.
%K A263691 nonn
%O A263691 1,2
%A A263691 _R. H. Hardin_, Oct 23 2015