A235170 Number of (n+1) X (2+1) 0..7 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).

1528, 8380, 45776, 250708, 1373616, 7533616, 41341624, 227070556, 1247903536, 6864076036, 37776977112, 208088450896, 1146857308352, 6326173721932, 34914806997296, 192860272424436, 1065880416716656, 5895663649023664

Offset

1,1

Links

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

Formula

Empirical: a(n) = 19*a(n-1) +34*a(n-2) -2719*a(n-3) +8988*a(n-4) +156665*a(n-5) -916999*a(n-6) -4550486*a(n-7) +40037121*a(n-8) +64400627*a(n-9) -1012400300*a(n-10) -148677233*a(n-11) +16600041004*a(n-12) -9873660689*a(n-13) -189875213441*a(n-14) +187284339366*a(n-15) +1593590554819*a(n-16) -1874014494735*a(n-17) -10158650544956*a(n-18) +12545534952885*a(n-19) +50324143130662*a(n-20) -60649685406985*a(n-21) -196489095492359*a(n-22) +219272447037552*a(n-23) +609171221202828*a(n-24) -603073067708424*a(n-25) -1502594545151892*a(n-26) +1270051970766120*a(n-27) +2940961682306376*a(n-28) -2045313082168560*a(n-29) -4535601595588512*a(n-30) +2497426659701280*a(n-31) +5448277567918080*a(n-32) -2274890615189568*a(n-33) -5012380431150912*a(n-34) +1506311626822272*a(n-35) +3449065504346496*a(n-36) -697075003450368*a(n-37) -1716839475671808*a(n-38) +212360144961024*a(n-39) +588874155660288*a(n-40) -38772262462464*a(n-41) -129032521869312*a(n-42) +3632324124672*a(n-43) +15786025500672*a(n-44) -130606940160*a(n-45) -783641640960*a(n-46)

Example

Some solutions for n=3:
  0 1 3   7 6 3   2 5 7   3 6 1   2 5 2   0 2 5   1 0 1
  2 7 5   5 0 1   4 3 1   4 3 2   5 4 5   5 3 2   0 3 0
  5 6 0   4 3 0   6 1 3   6 1 4   4 7 4   3 5 0   5 4 5
  2 7 5   7 2 3   4 3 1   3 2 1   7 6 7   1 7 6   6 1 6

Crossrefs

Column 2 of A235175.

Sequence in context: A236880 A226700 A226701 * A252414 A333721 A030061

Adjacent sequences: A235167 A235168 A235169 * A235171 A235172 A235173

Keyword

nonn

Author

R. H. Hardin, Jan 04 2014

Status

approved