A234481 T(n,k) is the number of (n+1) X (k+1) 0..7 arrays with every 2 X 2 subblock having its diagonal sum differing from its antidiagonal sum by 1 (constant-stress 1 X 1 tilings).

672, 7840, 7840, 95872, 141728, 95872, 1200640, 2765648, 2765648, 1200640, 15217152, 56172656, 87871120, 56172656, 15217152, 194145280, 1165600828, 2941603932, 2941603932, 1165600828, 194145280, 2484815872, 24484032192

Offset

1,1

Comments

Table starts

672 7840 95872 1200640 15217152

7840 141728 2765648 56172656 1165600828

95872 2765648 87871120 2941603932 101383587816

1200640 56172656 2941603932 163999261180 9478559277180

15217152 1165600828 101383587816 9478559277180 924511268818064

194145280 24484032192 3555453917560 560119617963572 92612141125166316

2484815872 517788509004 125966139330824 33549726037031472

Links

R. H. Hardin, Table of n, a(n) for n = 1..60

Formula

Empirical for column k:

k=1: a(n) = 224*a(n-2) -10304*a(n-4) +96256*a(n-6) -80640*a(n-8).

k=2: [order 46].

Example

Some solutions for n=2, k=4:
  0 4 6 0 1      4 4 6 2 2      4 4 6 7 4      4 4 6 1 3
  0 5 6 1 3      0 1 4 1 0      0 1 4 6 4      4 5 6 2 5
  0 6 6 2 5      0 0 4 0 0      0 2 4 7 6      2 4 4 1 5

Crossrefs

Sequence in context: A245778 A245786 A321116 * A234476 A340864 A331666

Adjacent sequences: A234478 A234479 A234480 * A234482 A234483 A234484

Keyword

nonn,tabl

Author

R. H. Hardin, Dec 26 2013

Status

approved