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%I #6 Dec 27 2023 12:54:20
%S 1,17,5,15,23,43,79,184,380,830,1776,3815,8227,17737,38335,82673,
%T 178600,385419,832806,1798455,3885410,8392102,18129621,39164405,
%U 84609476,182786176,394886142,853110431,1843063212,3981796702,8602359868
%N Number of n X 4 0..1 arrays with every element equal to 0, 2, 3 or 6 king-move adjacent elements, with upper left element zero.
%C Column 4 of A297986.
%H R. H. Hardin, <a href="/A297982/b297982.txt">Table of n, a(n) for n = 1..210</a>
%F Empirical: a(n) = 2*a(n-1) +2*a(n-2) -3*a(n-3) +2*a(n-4) -3*a(n-5) -9*a(n-6) -3*a(n-7) -3*a(n-8) +17*a(n-9) +13*a(n-10) +11*a(n-11) -5*a(n-12) -14*a(n-13) -a(n-14) +7*a(n-15) +10*a(n-16) -8*a(n-17) -12*a(n-18) -3*a(n-19) -5*a(n-20) +3*a(n-21) +2*a(n-22) for n>28.
%e Some solutions for n=7
%e ..0..0..1..1. .0..0..0..0. .0..0..0..0. .0..0..1..1. .0..1..1..1
%e ..1..0..0..1. .0..1..1..0. .0..1..1..0. .0..1..0..1. .0..0..1..0
%e ..1..1..1..0. .1..0..0..1. .0..1..0..1. .1..1..0..1. .0..1..1..1
%e ..0..0..0..1. .0..1..1..0. .1..0..0..1. .1..0..0..1. .1..0..0..0
%e ..0..1..1..0. .1..0..0..0. .1..1..1..0. .1..0..1..1. .0..1..1..0
%e ..1..0..0..1. .0..1..1..1. .0..0..0..1. .1..0..1..0. .0..1..0..1
%e ..1..1..1..1. .0..0..1..0. .1..0..1..1. .1..1..0..0. .0..0..1..1
%Y Cf. A297986.
%K nonn
%O 1,2
%A _R. H. Hardin_, Jan 10 2018