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A220575 Equals one maps: number of nX4 binary arrays indicating the locations of corresponding elements equal to exactly one of their horizontal and antidiagonal neighbors in a random 0..1 nX4 array.

%I A220575 #6 Jul 23 2025 01:14:27
%S A220575 8,115,1441,17505,205323,2352642,26616961,299065708,3347252663,
%T A220575 37378135504,416811197294,4643851898712,51709572437898,
%U A220575 575575826236700,6405129188993734,71266042324237205,792848605905100847
%N A220575 Equals one maps: number of nX4 binary arrays indicating the locations of corresponding elements equal to exactly one of their horizontal and antidiagonal neighbors in a random 0..1 nX4 array.
%C A220575 Column 4 of A220579
%H A220575 R. H. Hardin, <a href="/A220575/b220575.txt">Table of n, a(n) for n = 1..210</a>
%F A220575 Empirical: a(n) = 49*a(n-1) -1058*a(n-2) +13352*a(n-3) -109857*a(n-4) +620213*a(n-5) -2449435*a(n-6) +6704400*a(n-7) -12020996*a(n-8) +11403651*a(n-9) +1989496*a(n-10) -18274416*a(n-11) +12779735*a(n-12) +13888615*a(n-13) -21466582*a(n-14) -4814175*a(n-15) +19770698*a(n-16) +1111627*a(n-17) -21069650*a(n-18) +16193684*a(n-19) -921063*a(n-20) -11095317*a(n-21) +11666405*a(n-22) -3274482*a(n-23) -1162160*a(n-24) +1220233*a(n-25) -1400204*a(n-26) +728140*a(n-27) -62411*a(n-28) +67213*a(n-29) -17664*a(n-30) -12975*a(n-31) -10189*a(n-32) +5572*a(n-33) -704*a(n-34) +256*a(n-35) for n>36
%e A220575 Some solutions for n=3
%e A220575 ..0..1..0..1....1..0..1..0....1..1..1..1....1..0..1..0....1..0..1..1
%e A220575 ..0..1..1..0....1..1..0..1....1..0..0..1....0..0..0..1....1..0..0..1
%e A220575 ..1..0..1..0....0..1..0..1....0..1..0..1....1..1..0..0....1..1..0..1
%K A220575 nonn
%O A220575 1,1
%A A220575 _R. H. Hardin_ Dec 16 2012