A256741 - OEIS

%I #8 Dec 20 2018 23:07:06

%S 153,393,857,2065,5255,12914,31032,75634,185630,453792,1107035,

%T 2701934,6602744,16133440,39398362,96225937,235055049,574159002,

%U 1402439544,3425537766,8367239407,20438044264,49921902827,121939228872,297849461916

%N Number of (n+2) X (1+2) 0..1 arrays with no 3 x 3 subblock diagonal sum 3 and no antidiagonal sum 3 and no row sum 0 and no column sum 0.

%H R. H. Hardin, <a href="/A256741/b256741.txt">Table of n, a(n) for n = 1..210</a>

%F Empirical: a(n) = a(n-1) + 2*a(n-2) + 5*a(n-3) + a(n-5) - 14*a(n-6) - 19*a(n-7) + 3*a(n-8) + 3*a(n-9) for n>12.

%F Empirical g.f.: x*(153 + 240*x + 158*x^2 - 343*x^3 - 489*x^4 - 909*x^5 - 968*x^6 + 51*x^7 + 303*x^8 + 34*x^9 - 46*x^10 + 8*x^11) / (1 - x - 2*x^2 - 5*x^3 - x^5 + 14*x^6 + 19*x^7 - 3*x^8 - 3*x^9). - _Colin Barker_, Dec 20 2018

%e Some solutions for n=4:

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

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

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

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

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

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

%Y Column 1 of A256748.

%K nonn

%O 1,1

%A _R. H. Hardin_, Apr 09 2015