A231258 Number of (n+1) X (3+1) 0..2 arrays with no element unequal to a strict majority of its horizontal and antidiagonal neighbors, with values 0..2 introduced in row major order.
4, 32, 304, 2982, 29366, 289230, 2848550, 28054534, 276301638, 2721223974, 26800640678, 263952669990, 2599602461350, 25602820961958, 252155647340198, 2483416596612262, 24458536057349286, 240885877498412198
Offset: 1
Keywords
Examples
Some solutions for n=3: ..0..0..0..0....0..0..1..1....0..0..1..1....0..0..0..0....0..0..0..0 ..0..0..0..0....0..1..1..2....0..1..0..0....1..1..1..1....0..0..1..1 ..1..1..0..0....0..0..2..2....1..0..0..2....0..0..1..1....1..1..1..2 ..1..0..0..0....0..0..0..0....0..0..2..2....0..1..1..1....2..2..2..2
Links
- R. H. Hardin, Table of n, a(n) for n = 1..210
Formula
Empirical: a(n) = 17*a(n-1) -96*a(n-2) +308*a(n-3) -628*a(n-4) +800*a(n-5) -656*a(n-6) +256*a(n-7).
Empirical g.f.: 2*x*(2 - 18*x + 72*x^2 - 173*x^3 + 256*x^4 - 228*x^5 + 128*x^6) / ((1 - x)*(1 - 16*x + 80*x^2 - 228*x^3 + 400*x^4 - 400*x^5 + 256*x^6)). - Colin Barker, Feb 16 2018
Comments