A234438 Number of (n+1) X (3+1) 0..2 arrays with every 2 X 2 subblock having its diagonal sum differing from its antidiagonal sum by 1 (constant-stress 1 X 1 tilings).

448, 2804, 17200, 108404, 666880, 4221580, 26023136, 165444308, 1021780992, 6523295060, 40358959904, 258707287924, 1603224318880, 10317081808148, 64032676563232, 413605116397892, 2570619151590496, 16663502963008084

Offset

1,1

Links

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

Formula

Empirical: a(n) = 119*a(n-2) -4884*a(n-4) +76112*a(n-6) -295366*a(n-8) +424128*a(n-10) -242512*a(n-12) +58736*a(n-14) -4992*a(n-16).

Example

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

Crossrefs

Column 3 of A234443.

Sequence in context: A346514 A194648 A348344 * A048632 A366815 A234428

Adjacent sequences: A234435 A234436 A234437 * A234439 A234440 A234441

Keyword

nonn

Author

R. H. Hardin, Dec 26 2013

Status

approved