A234134 Number of (n+1) X (2+1) 0..3 arrays with every 2 X 2 subblock having the sum of the absolute values of all six edge and diagonal differences equal to 9.

80, 152, 296, 680, 1544, 4040, 9992, 28040, 72200, 209672, 549896, 1623560, 4294664, 12782600, 33951752, 101455880, 270016520, 808464392, 2153791496, 6455058440, 17205067784, 51589988360, 137539682312, 412518285320, 1099914412040

Offset

1,1

Links

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

Formula

Empirical: a(n) = 3*a(n-1) + 8*a(n-2) - 30*a(n-3) + 4*a(n-4) + 48*a(n-5) - 32*a(n-6).

Empirical g.f.: 8*x*(10 - 11*x - 100*x^2 + 122*x^3 + 172*x^4 - 200*x^5) / ((1 - x)*(1 - 2*x)*(1 - 2*x^2)*(1 - 8*x^2)). - Colin Barker, Oct 13 2018

Example

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

Crossrefs

Column 2 of A234140.

Sequence in context: A202440 A248432 A107931 * A134769 A371150 A295593

Adjacent sequences: A234131 A234132 A234133 * A234135 A234136 A234137

Keyword

nonn

Author

R. H. Hardin, Dec 19 2013

Status

approved