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%I #4 Nov 17 2015 15:33:21
%S 1,6,16,45,133,400,1204,3561,10554,31493,93784,278862,829809,2469737,
%T 7349616,21870896,65083321,193678264,576359005,1715146434,5103989104,
%U 15188659597,45198999981,134504868528,400264674436,1191122820729
%N Number of (n+1)X(3+1) arrays of permutations of 0..n*4+3 with each element having directed index change -1,1 -1,2 1,0 or 0,-1.
%C Column 3 of A264550.
%H R. H. Hardin, <a href="/A264545/b264545.txt">Table of n, a(n) for n = 1..210</a>
%F Empirical: a(n) = 2*a(n-1) +10*a(n-3) -4*a(n-4) +8*a(n-5) -25*a(n-6) -4*a(n-8) +33*a(n-9) +4*a(n-10) -4*a(n-11) -10*a(n-12) -2*a(n-13) +a(n-15)
%e Some solutions for n=4
%e ..1..2..5..6....1..2..3..5....1..2..3..5....1..4..3..6....1..2..3..5
%e ..0..8..9..3....0..6..7.10....0..8..9.10....0..8..2.10....0..6..7..9
%e ..4.10.12..7....4.12.11.14....4.12..6..7....9..5.12..7....4.10.11.14
%e .13.14.16.11....8..9.16.18...13.14.16.11...13.14.16.11....8.16.17.18
%e .17.18.19.15...17.13.19.15...17.18.19.15...17.18.19.15...12.13.19.15
%Y Cf. A264550.
%K nonn
%O 1,2
%A _R. H. Hardin_, Nov 17 2015
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