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A207695 Number of 4Xn 0..1 arrays avoiding 0 0 0 and 0 1 0 horizontally and 0 0 1 and 1 1 1 vertically.

%I A207695 #7 Jul 22 2025 20:41:10
%S A207695 9,81,144,256,768,2304,5856,14884,42700,122500,320600,839056,2361448,
%T A207695 6646084,17633520,46785600,130315680,362978704,970889920,2596921600,
%U A207695 7186175360,19885512256,53475523456,143804774656,396160887744
%N A207695 Number of 4Xn 0..1 arrays avoiding 0 0 0 and 0 1 0 horizontally and 0 0 1 and 1 1 1 vertically.
%C A207695 Row 4 of A207693
%H A207695 R. H. Hardin, <a href="/A207695/b207695.txt">Table of n, a(n) for n = 1..210</a>
%F A207695 Empirical: a(n) = 2*a(n-3) +64*a(n-4) +16*a(n-5) +4*a(n-6) -20*a(n-7) -1112*a(n-8) -324*a(n-9) +40*a(n-10) -136*a(n-11) +7516*a(n-12) +2032*a(n-13) -192*a(n-14) +1936*a(n-15) -23584*a(n-16) -4720*a(n-17) -5888*a(n-19) +37360*a(n-20) +3968*a(n-21) +480*a(n-22) +6464*a(n-23) -29872*a(n-24) -704*a(n-25) -256*a(n-26) -2592*a(n-27) +11072*a(n-28) -256*a(n-29) -64*a(n-30) +320*a(n-31) -1600*a(n-32) +64*a(n-33) +64*a(n-36) for n>39
%e A207695 Some solutions for n=4
%e A207695 ..1..0..0..1....0..1..1..0....0..1..1..0....1..0..1..1....1..1..1..0
%e A207695 ..0..1..1..0....1..0..0..1....1..0..1..1....1..1..0..0....1..0..0..1
%e A207695 ..1..0..0..1....1..1..1..0....1..1..0..0....0..1..1..1....0..1..1..0
%e A207695 ..0..1..1..0....0..0..1..1....0..0..1..1....0..0..1..1....1..0..1..1
%K A207695 nonn
%O A207695 1,1
%A A207695 _R. H. Hardin_ Feb 19 2012