A235313 Number of (n+1) X (2+1) 0..6 arrays with every 2 X 2 subblock having its diagonal sum differing from its antidiagonal sum by 7 (constant-stress 1 X 1 tilings).

392, 1120, 2744, 8392, 22568, 71896, 206360, 675064, 2026472, 6751000, 20907224, 70560952, 223435688, 761260696, 2450452760, 8407382584, 27402409832, 94504374040, 311023311704, 1076774857912, 3571073152808, 12398475609496

Offset

1,1

Comments

Column 2 of A235319.

Links

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

Formula

Empirical: a(n) = 4*a(n-1) +47*a(n-2) -200*a(n-3) -901*a(n-4) +4204*a(n-5) +8957*a(n-6) -48440*a(n-7) -47194*a(n-8) +334096*a(n-9) +101948*a(n-10) -1410080*a(n-11) +170136*a(n-12) +3549696*a(n-13) -1446912*a(n-14) -4861440*a(n-15) +2954880*a(n-16) +2764800*a(n-17) -2073600*a(n-18).

Example

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

Crossrefs

Sequence in context: A235188 A248022 A261379 * A203917 A180295 A166988

Adjacent sequences: A235310 A235311 A235312 * A235314 A235315 A235316

Keyword

nonn

Author

R. H. Hardin, Jan 05 2014

Status

approved