A235084 Number of (n+1) X (5+1) 0..4 arrays with every 2 X 2 subblock having its diagonal sum differing from its antidiagonal sum by 4, with no adjacent elements equal (constant-stress tilted 1 X 1 tilings).

1078, 2002, 3610, 7046, 13446, 27218, 53882, 111782, 226726, 478402, 986794, 2108630, 4404870, 9510434, 20077706, 43752230, 93259894, 205022194, 441124138, 978176486, 2124530262, 4751604194, 10419142682, 23500946774, 52030658038

Offset

1,1

Links

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

Formula

Empirical: a(n) = 6*a(n-1) +4*a(n-2) -87*a(n-3) +90*a(n-4) +450*a(n-5) -830*a(n-6) -936*a(n-7) +2737*a(n-8) +408*a(n-9) -4078*a(n-10) +891*a(n-11) +2766*a(n-12) -816*a(n-13) -904*a(n-14) +180*a(n-15) +120*a(n-16).

Example

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

Crossrefs

Column 5 of A235087.

Sequence in context: A235959 A235570 A278652 * A274234 A023085 A351672

Adjacent sequences: A235081 A235082 A235083 * A235085 A235086 A235087

Keyword

nonn

Author

R. H. Hardin, Jan 03 2014

Status

approved