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Number of (n+1)X5 0..1 arrays with the number of rightwards and downwards edge increases in each 2X2 subblock differing from the number in all its horizontal and vertical neighbors
1

%I #5 Mar 31 2012 12:37:04

%S 238,146,220,376,528,784,1192,1792,2744,4140,6288,9468,14376,21666,

%T 32912,49640,75328,113718,172408,260440,394624,596448,903184,1365912,

%U 2067168,3127772,4731240,7161736,10828680,16397424,24784304,37541428,56725480

%N Number of (n+1)X5 0..1 arrays with the number of rightwards and downwards edge increases in each 2X2 subblock differing from the number in all its horizontal and vertical neighbors

%C Column 4 of A205072

%H R. H. Hardin, <a href="/A205068/b205068.txt">Table of n, a(n) for n = 1..210</a>

%F Empirical: a(n) = 3*a(n-2) -2*a(n-6) -3*a(n-8) -2*a(n-10) -3*a(n-12) +2*a(n-14) +5*a(n-16) +6*a(n-18) +6*a(n-20) +3*a(n-22) +a(n-24) for n>27

%e Some solutions for n=4

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

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

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

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

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

%K nonn

%O 1,1

%A _R. H. Hardin_ Jan 21 2012