A234328 Number of (n+1) X (3+1) 0..3 arrays with every 2 X 2 subblock having its diagonal sum differing from its antidiagonal sum by 1 (constant-stress 1 X 1 tilings).

2368, 25728, 287888, 3271560, 37234216, 425662432, 4858165384, 55631535036, 635692080136, 7287762748412, 83358262956160, 956674989178676, 10953011278383544, 125838143389011112, 1442087851946088992

Offset

1,1

Links

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

Formula

Empirical: a(n) = 507*a(n-2) -102295*a(n-4) +10646830*a(n-6) -635915377*a(n-8) +23832852746*a(n-10) -596280829182*a(n-12) +10371633339873*a(n-14) -128744093807520*a(n-16) +1159671655063068*a(n-18) -7660667577596808*a(n-20) +37368059037902308*a(n-22) -135219186772494408*a(n-24) +364034788822163472*a(n-26) -730004249849579520*a(n-28) +1089413122161376064*a(n-30) -1205481757762071168*a(n-32) +981742220067000064*a(n-34) -581000394777277440*a(n-36) +244895745327540224*a(n-38) -71316845470162944*a(n-40) +13706205520330752*a(n-42) -1618885433491456*a(n-44) +103796813856768*a(n-46) -2721872609280*a(n-48).

Example

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

Crossrefs

Column 3 of A234333.

Sequence in context: A186785 A185607 A068282 * A258520 A232906 A241933

Adjacent sequences: A234325 A234326 A234327 * A234329 A234330 A234331

Keyword

nonn

Author

R. H. Hardin, Dec 23 2013

Status

approved