A235185 Number of (n+1) X (7+1) 0..5 arrays with every 2 X 2 subblock having its diagonal sum differing from its antidiagonal sum by 5, with no adjacent elements equal (constant-stress tilted 1 X 1 tilings).

38064, 71244, 131120, 270056, 545768, 1204056, 2598040, 6019088, 13595968, 32649376, 76226184, 188095080, 450248824, 1134831824, 2770942400, 7103894688, 17636624776, 45860150152, 115538722392, 304148763792, 776705047872

Offset

1,1

Links

R. H. Hardin, Table of n, a(n) for n = 1..89

Formula

Empirical: a(n) = 4*a(n-1) +41*a(n-2) -177*a(n-3) -709*a(n-4) +3405*a(n-5) +6658*a(n-6) -37423*a(n-7) -35857*a(n-8) +259792*a(n-9) +100713*a(n-10) -1189883*a(n-11) -44519*a(n-12) +3652705*a(n-13) -650588*a(n-14) -7506845*a(n-15) +2237158*a(n-16) +10206566*a(n-17) -3478912*a(n-18) -9024208*a(n-19) +2879248*a(n-20) +5075680*a(n-21) -1279200*a(n-22) -1728912*a(n-23) +283680*a(n-24) +319968*a(n-25) -24192*a(n-26) -24192*a(n-27).

Example

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

Crossrefs

Column 7 of A235186.

Sequence in context: A168628 A178286 A187938 * A172842 A068077 A094427

Adjacent sequences: A235182 A235183 A235184 * A235186 A235187 A235188

Keyword

nonn

Author

R. H. Hardin, Jan 04 2014

Status

approved