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Number of 5Xn 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.
1

%I #4 Apr 21 2018 13:15:07

%S 16,1,16,4,64,25,368,201,2545,1855,21082,17922,193932,178310,1883444,

%T 1798105,18748029,18258149,188640260,186011969,1906833092,1898120576,

%U 19312818727,19383847701,195770541009,198022534325,1985235845500

%N Number of 5Xn 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 Row 5 of A303325.

%H R. H. Hardin, <a href="/A303327/b303327.txt">Table of n, a(n) for n = 1..210</a>

%F Empirical: a(n) = 6*a(n-1) +12*a(n-2) -129*a(n-3) +69*a(n-4) +842*a(n-5) -1297*a(n-6) -839*a(n-7) +3412*a(n-8) -9036*a(n-9) +11871*a(n-10) +17108*a(n-11) -45954*a(n-12) +47570*a(n-13) -53012*a(n-14) -66076*a(n-15) +203444*a(n-16) -165552*a(n-17) +190584*a(n-18) +4296*a(n-19) -282112*a(n-20) +206832*a(n-21) -309856*a(n-22) +208160*a(n-23) -21344*a(n-24) +101312*a(n-25) -1024*a(n-26) +22336*a(n-27) -32256*a(n-28) +2560*a(n-29) -2816*a(n-30) +2816*a(n-31) +1536*a(n-32) +1024*a(n-33) -1024*a(n-34) for n>35

%e Some solutions for n=5

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

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

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

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

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

%Y Cf. A303325.

%K nonn

%O 1,1

%A _R. H. Hardin_, Apr 21 2018