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%I #9 Jan 02 2019 11:26:42
%S 1,2,5,9,11,19,27,44,65,104,155,246,370,582,882,1379,2100,3270,4997,
%T 7758,11885,18413,28258,43714,67171,103801,159643,246515,379373,
%U 585502,901460,1390734,2141907,3303555,5089046,7847557,12090913,18642253,28725828
%N Number of length n arrays of permutations of 0..n-1 with each element moved by -2 to 2 places and with no two consecutive increases.
%H R. H. Hardin, <a href="/A263637/b263637.txt">Table of n, a(n) for n = 1..210</a>
%F Empirical: a(n) = 2*a(n-2) + a(n-3) - a(n-5) for n>9.
%F Empirical g.f.: x*(1 + x - x^2)*(1 + x + 3*x^2 + 2*x^3 - x^5 - x^6) / (1 - 2*x^2 - x^3 + x^5). - _Colin Barker_, Jan 02 2019
%e Some solutions for n=6:
%e ..2....1....0....0....0....1....0....1....1....1....1....0....0....2....2....2
%e ..1....0....3....2....3....3....2....0....2....3....2....2....3....0....1....0
%e ..0....4....1....1....2....0....1....4....0....0....0....1....1....3....0....4
%e ..4....3....5....5....1....4....4....2....4....5....5....5....4....1....5....1
%e ..3....2....2....3....5....2....3....5....3....2....3....4....2....5....4....5
%e ..5....5....4....4....4....5....5....3....5....4....4....3....5....4....3....3
%Y Column 2 of A263643.
%K nonn
%O 1,2
%A _R. H. Hardin_, Oct 22 2015
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