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A302631 Number of nX4 0..1 arrays with every element equal to 0, 1, 3 or 6 horizontally, diagonally or antidiagonally adjacent elements, with upper left element zero.

%I A302631 #4 Apr 10 2018 19:29:34
%S A302631 5,17,14,33,101,248,657,1841,4892,13020,35447,95226,255042,688238,
%T A302631 1852413,4976015,13395869,36053423,96953152,260865015,701948030,
%U A302631 1888295155,5080237927,13668712238,36773414080,98934258153,266178278368
%N A302631 Number of nX4 0..1 arrays with every element equal to 0, 1, 3 or 6 horizontally, diagonally or antidiagonally adjacent elements, with upper left element zero.
%C A302631 Column 4 of A302635.
%H A302631 R. H. Hardin, <a href="/A302631/b302631.txt">Table of n, a(n) for n = 1..210</a>
%F A302631 Empirical: a(n) = a(n-1) +2*a(n-2) +9*a(n-3) -12*a(n-5) -13*a(n-6) +2*a(n-7) +17*a(n-8) +13*a(n-9) -6*a(n-10) -16*a(n-11) -12*a(n-12) +6*a(n-13) +12*a(n-14) +5*a(n-15) -8*a(n-16) -10*a(n-17) -4*a(n-18) +3*a(n-19) +3*a(n-20) +a(n-21) for n>25
%e A302631 Some solutions for n=5
%e A302631 ..0..1..0..1. .0..1..0..1. .0..1..0..1. .0..1..0..1. .0..1..1..0
%e A302631 ..0..1..0..0. .0..1..1..0. .0..1..1..0. .0..1..0..1. .1..0..1..0
%e A302631 ..0..1..0..1. .1..0..1..0. .1..0..1..0. .1..0..0..1. .1..0..1..0
%e A302631 ..0..1..0..1. .1..0..1..0. .1..0..1..0. .1..0..1..0. .1..0..1..0
%e A302631 ..0..1..1..0. .1..0..0..1. .1..1..0..0. .1..0..1..0. .1..0..0..1
%Y A302631 Cf. A302635.
%K A302631 nonn
%O A302631 1,1
%A A302631 _R. H. Hardin_, Apr 10 2018