A235288 Number of (n+1) X (7+1) 0..3 arrays with every 2 X 2 subblock having its diagonal sum differing from its antidiagonal sum by 4 (constant-stress 1 X 1 tilings).

836, 968, 1108, 1400, 1724, 2408, 3220, 4952, 7196, 12008, 18868, 33560, 56444, 105128, 186580, 358232, 660956, 1292648, 2448628, 4839320, 9327164, 18539048, 36139540, 72049112, 141513116, 282566888, 557838388, 1114758680, 2208549884

Offset

1,1

Comments

Column 7 of A235289.

Links

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

Formula

Empirical: a(n) = 3*a(n-1) +3*a(n-2) -15*a(n-3) +4*a(n-4) +18*a(n-5) -12*a(n-6).

Example

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

Crossrefs

Sequence in context: A236741 A113856 A245947 * A162945 A138850 A357326

Adjacent sequences: A235285 A235286 A235287 * A235289 A235290 A235291

Keyword

nonn

Author

R. H. Hardin, Jan 05 2014

Status

approved