A231397 Number of (1+1) X (n+1) 0..2 arrays with no element unequal to a strict majority of its horizontal, diagonal and antidiagonal neighbors, with values 0..2 introduced in row major order.
3, 7, 14, 33, 78, 189, 482, 1225, 3238, 8565, 23114, 62657, 171342, 470573, 1297330, 3586745, 9934454, 27559269, 76525210, 212662577, 591289630, 1644693789, 4576035586, 12734509097, 35443628358, 98659578197, 274645954794
Offset: 1
Keywords
Examples
Some solutions for n=5: ..0..1..1..1..1..2....0..1..0..1..0..0....0..0..1..1..0..0....0..0..1..1..0..0 ..0..0..1..1..2..2....1..0..1..0..1..1....0..0..1..1..1..0....0..0..1..1..0..0
Links
- R. H. Hardin, Table of n, a(n) for n = 1..210
Crossrefs
Row 1 of A231396.
Formula
Empirical: a(n) = 4*a(n-1) + a(n-2) - 16*a(n-3) + 4*a(n-4) + 24*a(n-5) - 16*a(n-6).
Empirical g.f.: x*(3 - 5*x - 17*x^2 + 18*x^3 + 32*x^4 - 32*x^5) / ((1 - x)*(1 - 2*x)*(1 - x - 6*x^2 + 8*x^4)). - Colin Barker, Sep 28 2018