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%I #8 Jan 08 2019 08:19:34
%S 6,38,211,1224,7177,41622,241432,1401492,8132167,47182878,273763030,
%T 1588400232,9215985850,53471653248,310245343849,1800059031396,
%U 10444031588569,60596786462766,351585536645329,2039916562746852
%N Number of (n+1) X (4+1) arrays of permutations of 0..n*5+4 with each element having directed index change -1,1 0,-1 0,1 or 1,0.
%H R. H. Hardin, <a href="/A264502/b264502.txt">Table of n, a(n) for n = 1..210</a>
%F Empirical: a(n) = 6*a(n-1) - 5*a(n-2) + 36*a(n-3) - 72*a(n-4) - 243*a(n-6) for n>7.
%F Empirical g.f.: x*(6 + 2*x + 13*x^2 - 68*x^3 - 48*x^4 - 180*x^5 + 171*x^6) / ((1 - x - 9*x^3)*(1 - 5*x - 27*x^3)). - _Colin Barker_, Jan 08 2019
%e Some solutions for n=4:
%e ..1..5..6..4..3....1..2..6..4..3....1..2..6..4..8....1..0..3..4..8
%e ..0..7..2..9..8....0..7.11..9..8....0.10.11..3.13....6.10..2..7.13
%e .11.15.13.12.18....5.12.16.17.13....5.12..7.14..9....5.15.11.12..9
%e .10.20.16.19.14...10.20.18.19.14...16.20.21.17.18...16.20.18.17.14
%e .21.22.17.24.23...15.22.21.24.23...15.22.23.24.19...21.22.23.24.19
%Y Column 4 of A264506.
%K nonn
%O 1,1
%A _R. H. Hardin_, Nov 15 2015
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