A219151 - OEIS

%I #7 Jul 25 2018 08:06:00

%S 4,9,32,104,360,1234,4224,14421,49292,168568,576373,1970380,6736149,

%T 23030217,78737741,269190899,920316854,3146418782,10757120910,

%U 36776888782,125734293267,429865563961,1469642274654,5024473730153

%N Unchanging value maps: number of n X 3 binary arrays indicating the locations of corresponding elements unequal to no horizontal, antidiagonal or vertical neighbor in a random 0..1 n X 3 array.

%C Column 3 of A219156.

%H R. H. Hardin, <a href="/A219151/b219151.txt">Table of n, a(n) for n = 1..210</a>

%F Empirical: a(n) = 4*a(n-1) - 6*a(n-2) + 14*a(n-3) - 2*a(n-4) + a(n-5) + 11*a(n-6) - 9*a(n-7) + 6*a(n-8) - 3*a(n-9) - 4*a(n-10).

%F Empirical g.f.: x*(4 - 7*x + 20*x^2 - 26*x^3 + 18*x^4 - 16*x^5 + 3*x^6 + 2*x^7 - 3*x^8) / ((1 - x + x^2)*(1 - 3*x + 2*x^2 - 9*x^3 - 9*x^4 - x^5 - 3*x^6 + 7*x^7 + 4*x^8)). - _Colin Barker_, Jul 25 2018

%e Some solutions for n=3:

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

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

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

%Y Cf. A219156.

%K nonn

%O 1,1

%A _R. H. Hardin_, Nov 12 2012