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 A208836 Number of n X 4 0..1 arrays avoiding 0 0 0 and 0 0 1 horizontally and 0 1 1 and 1 1 0 vertically. 2

%I

%S 10,100,282,855,3010,11242,44275,179032,737550,3070375,12868830,

%T 54154926,228475507,965411356,4083220786,17280246775,73157026602,

%U 309784875682,1311973439667,5556832891632,23537091290566,99699402777415

%N Number of n X 4 0..1 arrays avoiding 0 0 0 and 0 0 1 horizontally and 0 1 1 and 1 1 0 vertically.

%C Column 4 of A208840.

%H R. H. Hardin, <a href="/A208836/b208836.txt">Table of n, a(n) for n = 1..210</a>

%F Empirical: a(n) = 7*a(n-1) - 8*a(n-2) - 27*a(n-3) + 45*a(n-4) + 24*a(n-5) - 51*a(n-6) - 3*a(n-7) + 16*a(n-8) - a(n-9) - a(n-10) for n>11.

%F Empirical g.f.: x*(10 + 30*x - 338*x^2 - 49*x^3 + 1531*x^4 - 114*x^5 - 1834*x^6 + 200*x^7 + 612*x^8 - 63*x^9 - 41*x^10) / ((1 - x)*(1 + x)*(1 - 3*x + x^2)*(1 + x - x^2)*(1 - x - x^2)*(1 - 4*x - x^2)). - _Colin Barker_, Mar 07 2018

%e Some solutions for n=4:

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

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

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

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

%Y Cf. A208840.

%K nonn

%O 1,1

%A _R. H. Hardin_, Mar 01 2012

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Last modified January 27 17:36 EST 2022. Contains 350611 sequences. (Running on oeis4.)