A231856 Number of 2 X n 0..2 arrays with no element having a strict majority of its horizontal and antidiagonal neighbors equal to itself plus one mod 3, with upper left element zero (rock paper and scissors drawn positions).

3, 8, 34, 144, 612, 2613, 11159, 47675, 203696, 870316, 3718550, 15888022, 67883780, 290042861, 1239248291, 5294859950, 22623022401, 96659996189, 412993219856, 1764570725956, 7539372796546, 32213014377497, 137634565007885

Offset: 1

Author

R. H. Hardin, Nov 14 2013

Keywords

• nonn

Examples

			Some solutions for n=7:
..0..0..0..2..2..2..2....0..2..2..2..2..0..2....0..2..2..1..1..2..2
..1..1..2..2..2..0..1....2..2..2..2..1..1..1....1..1..1..1..0..0..0
		

Links

• R. H. Hardin, Table of n, a(n) for n = 1..210

Crossrefs

Row 2 of A231855.

Formula

Empirical: a(n) = 5*a(n-1) - 2*a(n-2) - 5*a(n-3) - a(n-4) + 10*a(n-5) - 3*a(n-6) - 3*a(n-7) + a(n-8) for n>9.

Empirical g.f.: x*(3 - 7*x + 5*x^3 + 3*x^4 - 11*x^5 + x^6 + 3*x^7 - x^8) / ((1 + x - x^3)*(1 - 6*x + 8*x^2 - 2*x^3 - 3*x^4 + x^5)). - Colin Barker, Oct 01 2018