%I #6 Jun 26 2022 04:33:09
%S 0,11,43,164,760,3425,15569,70323,318438,1441136,6522237,29519913,
%T 133601253,604673484,2736676090,12385962613,56057588893,253711291691,
%U 1148272314748,5196968663084,23520972129705,106453623089577
%N Number of 3 X n 0..1 arrays with every element equal to 1, 2 or 3 horizontally, diagonally or antidiagonally adjacent elements, with upper left element zero.
%C Row 3 of A302224.
%H R. H. Hardin, <a href="/A302226/b302226.txt">Table of n, a(n) for n = 1..210</a>
%F Empirical: a(n) = a(n-1) +17*a(n-2) +12*a(n-3) -59*a(n-4) -83*a(n-5) +10*a(n-6) +87*a(n-7) +108*a(n-8) +22*a(n-9) -104*a(n-10) -71*a(n-11) +2*a(n-13) +a(n-14) +2*a(n-15) for n>17.
%e Some solutions for n=5
%e ..0..0..1..0..0. .0..0..0..1..1. .0..0..0..0..1. .0..0..1..0..0
%e ..1..0..1..1..0. .0..0..1..1..0. .1..1..0..1..0. .1..0..1..1..0
%e ..1..1..0..0..1. .1..1..1..0..0. .1..1..1..0..1. .0..1..0..0..0
%Y Cf. A302224.
%K nonn
%O 1,2
%A _R. H. Hardin_, Apr 03 2018