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Number of 4Xn 0..2 arrays with no element equal to fewer vertical neighbors than horizontal neighbors, with new values 0..2 introduced in row major order
1

%I #4 Apr 20 2014 12:06:18

%S 14,326,7376,169982,3910194,90008909,2071815945,47690157718,

%T 1097756412666,25268747760871,581649645222695,13388725521741539,

%U 308188912773527912,7094058807175007496,163294876256510271215

%N Number of 4Xn 0..2 arrays with no element equal to fewer vertical neighbors than horizontal neighbors, with new values 0..2 introduced in row major order

%C Row 4 of A241370

%H R. H. Hardin, <a href="/A241373/b241373.txt">Table of n, a(n) for n = 1..210</a>

%F Empirical: a(n) = 32*a(n-1) -214*a(n-2) +26*a(n-3) +3879*a(n-4) -15470*a(n-5) +19107*a(n-6) +72463*a(n-7) -211026*a(n-8) +106996*a(n-9) +193844*a(n-10) -2000756*a(n-11) +412552*a(n-12) +8652096*a(n-13) -3035456*a(n-14) -10691648*a(n-15) +6530688*a(n-16) +2014720*a(n-17) -6114304*a(n-18) +2244608*a(n-19) +1933312*a(n-20) -720896*a(n-21) for n>23

%e Some solutions for n=4

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

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

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

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

%K nonn

%O 1,1

%A _R. H. Hardin_, Apr 20 2014