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A208145 Number of 6Xn 0..1 arrays avoiding 0 0 1 and 0 1 1 horizontally and 0 0 1 and 1 0 1 vertically.

%I A208145 #10 Jul 22 2025 21:11:49
%S A208145 12,144,756,3969,14112,50176,141120,396900,952560,2286144,4889808,
%T A208145 10458756,20490624,40144896,73389888,134165889,231891660,400800400,
%U A208145 661320660,1091179089,1731457728,2747437056,4216552704,6471237136
%N A208145 Number of 6Xn 0..1 arrays avoiding 0 0 1 and 0 1 1 horizontally and 0 0 1 and 1 0 1 vertically.
%C A208145 Row 6 of A208142
%H A208145 R. H. Hardin, <a href="/A208145/b208145.txt">Table of n, a(n) for n = 1..210</a>
%F A208145 Empirical: a(n) = 2*a(n-1) +10*a(n-2) -22*a(n-3) -44*a(n-4) +110*a(n-5) +110*a(n-6) -330*a(n-7) -165*a(n-8) +660*a(n-9) +132*a(n-10) -924*a(n-11) +924*a(n-13) -132*a(n-14) -660*a(n-15) +165*a(n-16) +330*a(n-17) -110*a(n-18) -110*a(n-19) +44*a(n-20) +22*a(n-21) -10*a(n-22) -2*a(n-23) +a(n-24).
%F A208145 Empirical: G.f. -x*(12 +120*x +x^23 -2*x^22 -10*x^21 +22*x^20 +44*x^19 -110*x^18 -110*x^17 +330*x^16 +165*x^15 -660*x^14 -132*x^13 +924*x^12 +25*x^11 -794*x^10 +818*x^9 +2110*x^8 +2960*x^7 +3070*x^6 +3910*x^5 +2310*x^4 +1281*x^3 +348*x^2) / ( (1+x)^11*(x-1)^13 ). - _R. J. Mathar_, Jul 03 2013
%e A208145 Some solutions for n=4
%e A208145 ..0..1..0..0....1..0..0..0....0..0..0..0....0..0..0..0....0..0..0..0
%e A208145 ..0..1..0..1....0..0..0..0....1..1..0..0....0..1..0..0....0..1..0..0
%e A208145 ..0..1..0..1....0..0..0..0....0..0..0..0....0..0..0..0....0..1..0..0
%e A208145 ..0..1..0..0....0..0..0..0....0..0..0..0....0..0..0..0....0..1..0..0
%e A208145 ..0..0..0..0....0..0..0..0....0..0..0..0....0..0..0..0....0..0..0..0
%e A208145 ..0..0..0..0....0..0..0..0....0..0..0..0....0..0..0..0....0..0..0..0
%K A208145 nonn
%O A208145 1,1
%A A208145 _R. H. Hardin_ Feb 23 2012