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

1,1

Links

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

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

Example

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

Crossrefs

Row 2 of A231855.

Sequence in context: A339315 A322303 A117722 * A024419 A303870 A186517

Adjacent sequences: A231853 A231854 A231855 * A231857 A231858 A231859

Keyword

nonn

Author

R. H. Hardin, Nov 14 2013

Status

approved