A235014 Number of (n+1) X (5+1) 0..4 arrays with every 2 X 2 subblock having its diagonal sum differing from its antidiagonal sum by 3, with no adjacent elements equal (constant-stress tilted 1 X 1 tilings).

1736, 2568, 4008, 6856, 12168, 23016, 44680, 90824, 189032, 407880, 900168, 2043496, 4730184, 11179080, 26815912, 65246024, 160397576, 397950312, 993981960, 2496937288, 6298923240, 15945371592, 40469357512, 102926663144

Offset

1,1

Links

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

Formula

Empirical: a(n) = 5*a(n-1) + a(n-2) - 38*a(n-3) + 33*a(n-4) + 97*a(n-5) - 127*a(n-6) - 88*a(n-7) + 154*a(n-8) + 12*a(n-9) - 48*a(n-10).

Empirical g.f.: 8*x*(217 - 764*x - 1321*x^2 + 6277*x^3 + 1772*x^4 - 18189*x^5 + 2134*x^6 + 21334*x^7 - 4260*x^8 - 7872*x^9) / ((1 - x)*(1 - 2*x)*(1 - x - x^2)*(1 - 2*x^2)*(1 - 3*x^2)*(1 - x - 4*x^2)). - Colin Barker, Oct 17 2018

Example

Some solutions for n=4:
  2 0 2 1 2 0    1 0 2 4 3 2    0 2 1 2 0 4    4 3 2 4 2 3
  1 2 1 3 1 2    2 4 3 2 4 0    1 0 2 0 1 2    0 2 4 3 4 2
  3 1 3 2 3 1    1 0 2 4 3 2    2 4 3 4 2 0    2 1 0 2 0 1
  1 2 1 3 1 2    2 4 3 2 4 0    1 0 2 0 1 2    4 0 2 1 2 0
  2 0 2 1 2 0    1 0 2 4 3 2    0 2 1 2 0 4    2 1 0 2 0 1

Crossrefs

Column 5 of A235017.

Sequence in context: A095847 A253696 A253703 * A185766 A179160 A043653

Adjacent sequences: A235011 A235012 A235013 * A235015 A235016 A235017

Keyword

nonn

Author

R. H. Hardin, Jan 02 2014

Status

approved