A234163 Number of (n+1) X (2+1) 0..4 arrays with every 2 X 2 subblock having its diagonal sum differing from its antidiagonal sum by 2 (constant-stress 1 X 1 tilings).

766, 4970, 32070, 208412, 1353986, 8846884, 57811490, 380032300, 2498158614, 16525702136, 109291218482, 727617468480, 4841329246098, 32438005700384, 217127834616758, 1463930354942564, 9855977995905954, 66852413995644068

Offset

1,1

Links

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

Formula

Empirical: a(n) = 17*a(n-1) +16*a(n-2) -1651*a(n-3) +5750*a(n-4) +45373*a(n-5) -252572*a(n-6) -278797*a(n-7) +2737923*a(n-8) +518738*a(n-9) -11300724*a(n-10) +169584*a(n-11) +18786600*a(n-12) -2246544*a(n-13) -13289184*a(n-14) +2960064*a(n-15) +3359232*a(n-16) -1119744*a(n-17).

Example

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

Crossrefs

Column 2 of A234169.

Sequence in context: A343705 A247486 A125109 * A159209 A045142 A115934

Adjacent sequences: A234160 A234161 A234162 * A234164 A234165 A234166

Keyword

nonn

Author

R. H. Hardin, Dec 20 2013

Status

approved