%I #4 Apr 13 2018 13:24:38
%S 4,25,75,220,731,2419,7900,25645,83685,273504,893195,2915411,9518108,
%T 31079021,101478805,331335348,1081839931,3532345439,11533574036,
%U 37658571753,122959986781,401480186136,1310884882811,4280209057195
%N Number of 3Xn 0..1 arrays with every element equal to 0, 1, 2, 4 or 5 horizontally, diagonally or antidiagonally adjacent elements, with upper left element zero.
%C Row 3 of A302820.
%H R. H. Hardin, <a href="/A302821/b302821.txt">Table of n, a(n) for n = 1..210</a>
%F Empirical: a(n) = 6*a(n-1) -9*a(n-2) +2*a(n-4) -18*a(n-5) +37*a(n-6) +34*a(n-7) +5*a(n-8) -52*a(n-9) -118*a(n-10) -24*a(n-11) +190*a(n-12) +10*a(n-13) -68*a(n-14) +12*a(n-15) for n>16
%e Some solutions for n=5
%e ..0..1..1..1..1. .0..1..1..1..0. .0..0..0..0..0. .0..1..0..0..0
%e ..0..1..0..1..0. .0..1..0..1..0. .0..0..0..0..0. .0..0..1..1..1
%e ..0..1..0..0..0. .0..1..1..1..0. .1..1..0..1..1. .1..1..0..1..0
%Y Cf. A302820.
%K nonn
%O 1,1
%A _R. H. Hardin_, Apr 13 2018