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A207173 Number of 5 X n 0..1 arrays avoiding 0 0 0 and 1 0 1 horizontally and 0 0 1 and 1 0 1 vertically. 1

%I #8 Jun 20 2018 14:26:15

%S 10,100,270,1161,3445,8455,26908,82861,228060,672760,2029041,5846337,

%T 17039101,50518174,147655795,430953736,1267685262,3717105229,

%U 10874111625,31898934243,93554384968,274033182253,803273682808,2355253402240

%N Number of 5 X n 0..1 arrays avoiding 0 0 0 and 1 0 1 horizontally and 0 0 1 and 1 0 1 vertically.

%C Row 5 of A207169.

%H R. H. Hardin, <a href="/A207173/b207173.txt">Table of n, a(n) for n = 1..210</a>

%F Empirical: a(n) = a(n-1) + 17*a(n-3) + 4*a(n-4) + 4*a(n-5) - 48*a(n-6) - 32*a(n-7) + 64*a(n-9) for n>11.

%F Empirical g.f.: x*(10 + 90*x + 170*x^2 + 721*x^3 + 544*x^4 - 20*x^5 - 2284*x^6 - 3216*x^7 - 800*x^8 + 3392*x^9 + 2304*x^10) / ((1 - 2*x - 8*x^3)*(1 + x + 2*x^2 - 5*x^3 - 6*x^4 + 8*x^6)). - _Colin Barker_, Jun 20 2018

%e Some solutions for n=4:

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

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

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

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

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

%Y Cf. A207169.

%K nonn

%O 1,1

%A _R. H. Hardin_, Feb 15 2012

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Last modified April 19 08:08 EDT 2024. Contains 371782 sequences. (Running on oeis4.)