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%I #10 Jan 06 2019 10:41:48
%S 3,21,95,557,3303,18725,105839,602365,3432551,19548549,111260799,
%T 633294925,3605196759,20523670997,116833710703,665088330013,
%U 3786103422919,21552938831269,122693118848735,698447387572077
%N Number of (2+1) X (n+1) arrays of permutations of 0..n*3+2 with each element having directed index change 0,0 1,1 0,-1 -1,1 or 0,-2.
%H R. H. Hardin, <a href="/A264246/b264246.txt">Table of n, a(n) for n = 1..210</a>
%F Empirical: a(n) = 3*a(n-1) + 8*a(n-2) + 24*a(n-3) + 88*a(n-4) + 88*a(n-5) + 24*a(n-6) - 552*a(n-7) - 352*a(n-8) - 96*a(n-9) for n>10.
%F Empirical g.f.: x*(3 + 12*x + 8*x^2 + 32*x^3 + 104*x^4 - 32*x^5 - 408*x^6 - 448*x^7 + 32*x^8 + 128*x^9) / (1 - 3*x - 8*x^2 - 24*x^3 - 88*x^4 - 88*x^5 - 24*x^6 + 552*x^7 + 352*x^8 + 96*x^9). - _Colin Barker_, Jan 06 2019
%e Some solutions for n=4:
%e ..0..1..2..3..4....1..2..4..7..8....0..2..4..7..8....1..2..3..4..8
%e ..5..7.11..8..9....5..0.11..9..3....6.10..1..9..3....6..0.11.12..9
%e .10.12..6.13.14...10.12..6.13.14...11..5.12.13.14...10..5.13..7.14
%Y Row 2 of A264244.
%K nonn
%O 1,1
%A _R. H. Hardin_, Nov 09 2015
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