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%I #8 Jan 07 2019 12:42:13
%S 18,120,936,7168,54720,418992,3204336,24514000,187528608,1434558960,
%T 10974201216,83950973056,642212998704,4912836726000,37582492431888,
%U 287500651922848,2199338537486832,16824622797993408,128705939150098368
%N Number of (n+1) X (4+1) arrays of permutations of 0..n*5+4 with each element having directed index change 0,0 0,2 1,0 or -1,-2.
%H R. H. Hardin, <a href="/A264360/b264360.txt">Table of n, a(n) for n = 1..210</a>
%F Empirical: a(n) = 3*a(n-1) + 28*a(n-2) + 57*a(n-3) + 10*a(n-4) - 24*a(n-5) + 8*a(n-6).
%F Empirical g.f.: 2*x*(9 + 33*x + 36*x^2 - 13*x^3 - 6*x^4 + 4*x^5) / (1 - 3*x - 28*x^2 - 57*x^3 - 10*x^4 + 24*x^5 - 8*x^6). - _Colin Barker_, Jan 07 2019
%e Some solutions for n=4:
%e ..0..1..2..3..4....0..1..2..3..4....7..8..2..1..4....0..1..2..3..4
%e ..5..6..7..8..9....5.13.14..8..7....0..6..5..3..9...12..6..7..8..9
%e .10.11.12.13.14...10..6.19.11..9...10.11.12.13.14....5.18.10.11.14
%e .15.16.24.18.19...15.23.12.18.17...22.16.17.18.19...22.16.17.13.19
%e .20.21.17.23.22...20.16.22.21.24...15.21.20.23.24...15.21.20.23.24
%Y Column 4 of A264364.
%K nonn
%O 1,1
%A _R. H. Hardin_, Nov 12 2015
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