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Number of 4Xn 0..1 arrays with no 1 equal to more than three of its horizontal, diagonal and antidiagonal neighbors.
1

%I #4 Mar 17 2017 12:03:36

%S 16,256,2837,35373,456316,5742620,72394838,916118713,11578902038,

%T 146303878883,1849120160189,23370319192081,295356801554484,

%U 3732805298242779,47176419243543777,596229278644402659

%N Number of 4Xn 0..1 arrays with no 1 equal to more than three of its horizontal, diagonal and antidiagonal neighbors.

%C Row 4 of A283857.

%H R. H. Hardin, <a href="/A283860/b283860.txt">Table of n, a(n) for n = 1..210</a>

%F Empirical: a(n) = 8*a(n-1) +28*a(n-2) +366*a(n-3) +386*a(n-4) -779*a(n-5) -7223*a(n-6) -24938*a(n-7) -38986*a(n-8) -8415*a(n-9) +26074*a(n-10) -17823*a(n-11) -21705*a(n-12) +40001*a(n-13) +40567*a(n-14) -22002*a(n-15) -44398*a(n-16) +15085*a(n-17) +24099*a(n-18) +3105*a(n-19) -1004*a(n-20) -3751*a(n-21) -1424*a(n-22) +52*a(n-23) +59*a(n-24) -894*a(n-25) -146*a(n-26) +193*a(n-27) -14*a(n-28)

%e Some solutions for n=4

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

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

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

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

%Y Cf. A283857.

%K nonn

%O 1,1

%A _R. H. Hardin_, Mar 17 2017