%I #4 Jan 12 2018 09:30:11
%S 2,13,19,30,53,92,149,250,426,809,1456,2602,4606,8096,14731,27112,
%T 49118,88604,159685,288458,526293,960108,1742179,3159153,5731030,
%U 10414879,18970871,34518779,62715041,113954032,207132787,376765957,685570021
%N Number of nX4 0..1 arrays with every element equal to 1, 2, 4 or 7 king-move adjacent elements, with upper left element zero.
%C Column 4 of A298093.
%H R. H. Hardin, <a href="/A298089/b298089.txt">Table of n, a(n) for n = 1..210</a>
%F Empirical: a(n) = 2*a(n-1) +a(n-2) -a(n-3) -2*a(n-4) +2*a(n-5) +4*a(n-6) -28*a(n-7) -3*a(n-8) +26*a(n-9) +22*a(n-10) +6*a(n-11) +7*a(n-12) +53*a(n-13) -42*a(n-14) -84*a(n-15) -64*a(n-16) -24*a(n-17) -3*a(n-18) +40*a(n-19) +101*a(n-20) +36*a(n-21) +51*a(n-22) +23*a(n-23) +75*a(n-24) -85*a(n-25) -129*a(n-26) +23*a(n-27) +6*a(n-28) -58*a(n-29) -108*a(n-30) +41*a(n-31) +87*a(n-32) +38*a(n-33) -2*a(n-34) -10*a(n-35) for n>40
%e Some solutions for n=7
%e ..0..0..1..1. .0..1..0..1. .0..0..1..1. .0..0..1..0. .0..0..1..0
%e ..1..1..0..0. .1..0..1..1. .1..0..1..0. .1..1..0..1. .1..1..0..1
%e ..0..0..0..1. .0..1..0..0. .1..1..1..0. .0..0..0..1. .1..0..1..0
%e ..1..1..0..1. .0..1..1..1. .1..1..1..0. .1..0..1..0. .1..1..1..0
%e ..0..0..1..0. .1..0..1..0. .1..0..1..0. .0..1..1..1. .1..1..1..0
%e ..0..1..0..1. .0..0..0..1. .1..1..0..1. .0..1..0..0. .1..0..1..0
%e ..0..0..0..1. .1..1..0..1. .0..0..1..0. .1..0..1..1. .0..0..1..1
%Y Cf. A298093.
%K nonn
%O 1,1
%A _R. H. Hardin_, Jan 12 2018
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