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Number of n X 4 0..1 arrays with no element less than a strict majority of its horizontal, diagonal and antidiagonal neighbors.
1

%I #6 Apr 26 2021 14:58:33

%S 7,107,865,7697,66499,571226,4944075,42759650,369356733,3191749214,

%T 27585602947,238391033438,2060118342038,17803462264679,

%U 153856523007378,1329613892196866,11490414159104930,99299276258131228,858136420916602390

%N Number of n X 4 0..1 arrays with no element less than a strict majority of its horizontal, diagonal and antidiagonal neighbors.

%C Column 4 of A231523.

%H R. H. Hardin, <a href="/A231519/b231519.txt">Table of n, a(n) for n = 1..210</a>

%F Empirical: a(n) = 7*a(n-1) +3*a(n-2) +117*a(n-3) -96*a(n-4) -500*a(n-5) -1683*a(n-6) -40*a(n-7) +4807*a(n-8) +6898*a(n-9) -181*a(n-10) -9621*a(n-11) -10107*a(n-12) -734*a(n-13) -9567*a(n-14) -4385*a(n-15) +24373*a(n-16) +1907*a(n-17) -17636*a(n-18) +2087*a(n-19) +6490*a(n-20) +1542*a(n-21) -233*a(n-22) -560*a(n-23) -36*a(n-24) for n > 25.

%e Some solutions for n=5

%e ..1..0..0..1....0..0..1..1....0..0..1..1....0..0..1..0....0..0..1..1

%e ..1..0..0..1....0..0..0..1....1..0..0..1....0..1..0..1....1..1..0..1

%e ..1..0..0..0....0..1..1..0....0..0..1..0....0..0..1..1....1..0..0..0

%e ..1..0..0..1....0..0..0..1....1..0..0..1....0..0..1..1....1..0..0..0

%e ..0..0..1..1....1..0..1..1....1..0..0..0....0..1..1..1....0..0..1..0

%Y Cf. A231523.

%K nonn

%O 1,1

%A _R. H. Hardin_, Nov 10 2013