A234560 Number of (n+1) X (4+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).

1954, 3384, 5710, 11982, 23830, 57210, 128614, 339234, 831334, 2348514, 6096550, 18108882, 48774790, 150230370, 414112774, 1309321074, 3662050534, 11801192514, 33312585190, 108877827282, 309161287750, 1021316064930, 2911094369734

Offset

1,1

Links

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

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 0      4 2 3 0 3      4 2 4 2 3      4 2 4 2 4
  2 1 2 0 2      1 3 0 1 0      1 3 1 3 0      0 2 0 2 0
  0 3 0 2 0      4 2 3 0 3      4 2 4 2 3      4 2 4 2 4
  4 3 4 2 4      2 4 1 2 1      2 4 2 4 1      0 2 0 2 0
  0 3 0 2 0      4 2 3 0 3      3 1 3 1 2      4 2 4 2 4
  2 1 2 0 2      2 4 1 2 1      1 3 1 3 0      1 3 1 3 1

Crossrefs

Column 4 of A234564.

Sequence in context: A249217 A155809 A116211 * A232389 A209946 A200857

Adjacent sequences: A234557 A234558 A234559 * A234561 A234562 A234563

Keyword

nonn

Author

R. H. Hardin, Dec 28 2013

Status

approved