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Number of nX5 0..2 arrays with top left element 0, horizontal differences mod 3 never 1, vertical differences mod 3 never -1, and antidiagonal differences never 0
1

%I #4 Sep 22 2013 09:52:45

%S 16,89,536,3357,21464,138645,899860,5852687,38099072,248105251,

%T 1615963560,10525963187,68565944112,446645329321,2909516286464,

%U 18953111619005,123464205731360,804270242627253,5239177554585924

%N Number of nX5 0..2 arrays with top left element 0, horizontal differences mod 3 never 1, vertical differences mod 3 never -1, and antidiagonal differences never 0

%C Column 5 of A229402

%H R. H. Hardin, <a href="/A229399/b229399.txt">Table of n, a(n) for n = 1..210</a>

%F Empirical: a(n) = 17*a(n-1) -120*a(n-2) +505*a(n-3) -1511*a(n-4) +3524*a(n-5) -6668*a(n-6) +10300*a(n-7) -12840*a(n-8) +12612*a(n-9) -9484*a(n-10) +5308*a(n-11) -2151*a(n-12) +615*a(n-13) -120*a(n-14) +15*a(n-15) -a(n-16)

%e Some solutions for n=4

%e ..0..2..1..1..1....0..2..1..1..1....0..2..1..1..0....0..0..0..2..1

%e ..1..0..2..2..1....1..0..2..2..2....1..0..2..2..1....1..1..0..0..2

%e ..1..1..0..2..1....1..0..0..0..2....2..1..0..2..2....2..1..1..1..0

%e ..2..1..0..2..2....1..1..1..0..0....0..2..1..0..0....2..2..2..1..1

%K nonn

%O 1,1

%A _R. H. Hardin_ Sep 22 2013