A258960 - OEIS

%I #8 Dec 23 2018 09:06:19

%S 158,344,274,467,614,951,1228,1951,2652,4261,5688,9170,12562,20311,

%T 27308,44158,60442,97842,131938,213491,291732,472335,638108,1032723,

%U 1409172,2281540,3086358,4995377,6808672,11023318,14926538,24160156,32902102

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

%H R. H. Hardin, <a href="/A258960/b258960.txt">Table of n, a(n) for n = 1..210</a>

%F Empirical: a(n) = a(n-1) + a(n-2) - a(n-3) + 4*a(n-4) - 4*a(n-5) - 3*a(n-6) + 3*a(n-7) for n>13.

%F Empirical g.f.: x*(158 + 186*x - 228*x^2 + 7*x^3 - 415*x^4 - 600*x^5 + 884*x^6 + 172*x^7 - 374*x^8 + 117*x^9 + 59*x^10 - 8*x^11 - 8*x^12) / ((1 - x)*(1 - x^2 - 4*x^4 + 3*x^6)). - _Colin Barker_, Dec 23 2018

%e Some solutions for n=4:

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

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

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

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

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

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

%Y Column 2 of A258966.

%K nonn

%O 1,1

%A _R. H. Hardin_, Jun 15 2015