A234562 Number of (n+1) X (6+1) 0..4 arrays with every 2 X 2 subblock having its diagonal sum differing from its antidiagonal sum by 4 (constant-stress 1 X 1 tilings).

17518, 24420, 33946, 57210, 94114, 187686, 358450, 810702, 1742578, 4339470, 10208626, 27473790, 69051154, 197748366, 520464850, 1563624222, 4244422258, 13213530990, 36597846706, 116923590270, 328074294994, 1067947652046

Offset

1,1

Links

R. H. Hardin, Table of n, a(n) for n = 1..141

Formula

Empirical: a(n) = 4*a(n-1) +30*a(n-2) -132*a(n-3) -331*a(n-4) +1720*a(n-5) +1530*a(n-6) -11280*a(n-7) -1324*a(n-8) +39136*a(n-9) -12360*a(n-10) -67968*a(n-11) +39456*a(n-12) +46080*a(n-13) -34560*a(n-14).

Example

Some solutions for n=5:
  0 3 0 2 1 2 0        4 1 3 1 3 1 4        3 2 4 2 2 2 4
  2 1 2 0 3 0 2        1 2 0 2 0 2 1        1 4 2 4 0 4 2
  1 4 1 3 2 3 1        3 0 2 0 2 0 3        3 2 4 2 2 2 4
  2 1 2 0 3 0 2        3 4 2 4 2 4 3        1 4 2 4 0 4 2
  0 3 0 2 1 2 0        3 0 2 0 2 0 3        3 2 4 2 2 2 4
  2 1 2 0 3 0 2        2 3 1 3 1 3 2        1 4 2 4 0 4 2

Crossrefs

Column 6 of A234564.

Sequence in context: A303996 A251641 A251638 * A321640 A083599 A049521

Adjacent sequences: A234559 A234560 A234561 * A234563 A234564 A234565

Keyword

nonn

Author

R. H. Hardin, Dec 28 2013

Status

approved