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%I #5 Nov 18 2015 20:30:58
%S 0,4,4,6,25,68,112,281,856,1674,3988,10508,23724,55897,136144,325584,
%T 765361,1829400,4401652,10407276,24816024,59395330,141247593,
%U 336608388,803177056,1914674361,4562063424,10876904302,25937972164,61813285608
%N Number of (n+1)X(3+1) arrays of permutations of 0..n*4+3 with each element having directed index change 1,0 0,-1 1,2 or -1,1.
%C Column 3 of A264583.
%H R. H. Hardin, <a href="/A264578/b264578.txt">Table of n, a(n) for n = 1..210</a>
%F Empirical: a(n) = 2*a(n-2) +10*a(n-3) +4*a(n-4) -4*a(n-5) -33*a(n-6) +4*a(n-7) +25*a(n-9) -8*a(n-10) +4*a(n-11) -10*a(n-12) -2*a(n-14) +a(n-15)
%e Some solutions for n=4
%e ..1..2..5..6....1..2..3..6....1..2..3..6....1..2..5..6....1..2..5..6
%e ..0..8..7..3....0..8..7.10....0..8..7.10....0..8..7..3....0..8..7..3
%e ..9.12..4.14....4..5.11.14....9..5..4.14....4.12.11.14....4.10.11.14
%e .13.16.10.11...13.16.17..9...13.16.17.11...13.16.10..9...13.16.17..9
%e .17.18.19.15...12.18.19.15...12.18.19.15...17.18.19.15...12.18.19.15
%Y Cf. A264583.
%K nonn
%O 1,2
%A _R. H. Hardin_, Nov 18 2015
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