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A303321 Number of nX4 0..1 arrays with every element equal to 0, 2, 4, 5 or 6 horizontally, diagonally or antidiagonally adjacent elements, with upper left element zero.

%I A303321 #4 Apr 21 2018 13:10:27
%S A303321 1,8,1,2,4,3,3,10,9,10,19,29,40,65,96,148,238,356,573,865,1381,2136,
%T A303321 3369,5245,8248,12925,20251,31889,49995,78599,123579,194464,305630,
%U A303321 481471,757704,1193056,1879551,2961524,4666170,7355683,11597513,18284922
%N A303321 Number of nX4 0..1 arrays with every element equal to 0, 2, 4, 5 or 6 horizontally, diagonally or antidiagonally adjacent elements, with upper left element zero.
%C A303321 Column 4 of A303325.
%H A303321 R. H. Hardin, <a href="/A303321/b303321.txt">Table of n, a(n) for n = 1..210</a>
%F A303321 Empirical: a(n) = 2*a(n-2) +4*a(n-3) +2*a(n-4) -3*a(n-5) -6*a(n-6) -10*a(n-7) -16*a(n-8) -9*a(n-9) +11*a(n-10) +35*a(n-11) +39*a(n-12) +30*a(n-13) +13*a(n-14) -6*a(n-15) -38*a(n-16) -66*a(n-17) -80*a(n-18) -55*a(n-19) -14*a(n-20) +25*a(n-21) +49*a(n-22) +76*a(n-23) +90*a(n-24) +67*a(n-25) +16*a(n-26) -30*a(n-27) -46*a(n-28) -37*a(n-29) -49*a(n-30) -51*a(n-31) -12*a(n-32) +47*a(n-33) +62*a(n-34) +14*a(n-35) -16*a(n-36) -7*a(n-37) -8*a(n-38) -35*a(n-39) -48*a(n-40) -18*a(n-41) +19*a(n-42) +33*a(n-43) +23*a(n-44) +16*a(n-45) +12*a(n-46) +a(n-47) -6*a(n-48) -11*a(n-49) -8*a(n-50) -3*a(n-51) -a(n-52) +2*a(n-53) +a(n-54) +a(n-55) for n>57
%e A303321 All solutions for n=5
%e A303321 ..0..0..0..1. .0..1..1..1. .0..1..0..1. .0..0..1..1
%e A303321 ..0..0..0..1. .0..1..1..1. .0..1..0..1. .0..0..1..1
%e A303321 ..0..1..0..1. .0..1..0..1. .0..1..0..1. .0..1..0..1
%e A303321 ..0..0..0..1. .0..1..1..1. .0..1..0..1. .0..0..1..1
%e A303321 ..0..0..0..1. .0..1..1..1. .0..1..0..1. .0..0..1..1
%Y A303321 Cf. A303325.
%K A303321 nonn
%O A303321 1,2
%A A303321 _R. H. Hardin_, Apr 21 2018