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%I #11 Jan 06 2019 10:44:40
%S 10,33,180,760,3653,16401,76330,348480,1607429,7373520,33925033,
%T 155833327,716445000,3292287537,15133013897,69549148120,319662372941,
%U 1469173559040,6752499229970,31034919432791,142639437485117
%N Number of (n+1) X (2+1) arrays of permutations of 0..n*3+2 with each element having directed index change 0,1 0,-1 0,2 1,0 or -1,0.
%H R. H. Hardin, <a href="/A264251/b264251.txt">Table of n, a(n) for n = 1..210</a>
%F Empirical: a(n) = a(n-1) + 16*a(n-2) + 9*a(n-3) - 29*a(n-4) - 9*a(n-5) + 16*a(n-6) - a(n-7) - a(n-8).
%F Empirical g.f.: x*(1 - x)*(10 + 33*x + 20*x^2 - 18*x^3 - 12*x^4 + 3*x^5 + x^6) / (1 - x - 16*x^2 - 9*x^3 + 29*x^4 + 9*x^5 - 16*x^6 + x^7 + x^8). - _Colin Barker_, Jan 06 2019
%e Some solutions for n=4:
%e ..3..2..5....3..4..5....1..2..0....3..2..5....1..0..5....1..2..0....1..0..5
%e ..0..1..4....0..1..2....6..3..4....0..1..4....6..3..2....6..5..4....4..3..2
%e ..9..8..6....9.10..7....7..8..5....7.10.11....7..4.11....3..8.11....7..8..6
%e .12..7.14....6.11..8...12.11.14....6..9..8...10..9..8...12..7.14...12..9.14
%e .13.10.11...13.14.12....9.10.13...13.14.12...13.14.12....9.10.13...13.10.11
%Y Column 2 of A264257.
%K nonn
%O 1,1
%A _R. H. Hardin_, Nov 09 2015
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