A234439 Number of (n+1) X (4+1) 0..2 arrays with every 2 X 2 subblock having its diagonal sum differing from its antidiagonal sum by 1 (constant-stress 1 X 1 tilings).

1680, 13676, 108404, 896112, 7165920, 59991972, 483370700, 4098064360, 33256428216, 285401797556, 2331380041352, 20236520658020, 166277888470420, 1458328058867824, 12043248971236632, 106601640805896728

Offset

1,1

Links

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

Formula

Empirical: a(n) = 19*a(n-1) +174*a(n-2) -5225*a(n-3) -579*a(n-4) +557372*a(n-5) -1736348*a(n-6) -28633611*a(n-7) +147097160*a(n-8) +701879450*a(n-9) -5215474532*a(n-10) -6448644414*a(n-11) +90991389225*a(n-12) -13155453655*a(n-13) -911859068299*a(n-14) +785985063499*a(n-15) +5750480317192*a(n-16) -7719561708652*a(n-17) -23967944021653*a(n-18) +42175716887542*a(n-19) +67283824235584*a(n-20) -150636045987035*a(n-21) -125392746919991*a(n-22) +373892366562458*a(n-23) +141881972068085*a(n-24) -664306804785765*a(n-25) -55299787514109*a(n-26) +857132068732641*a(n-27) -106700542512030*a(n-28) -806720994198218*a(n-29) +225446251980190*a(n-30) +551556767133038*a(n-31) -222526751973132*a(n-32) -270104055145308*a(n-33) +138509404758088*a(n-34) +92036096585608*a(n-35) -57527289381280*a(n-36) -20591630958048*a(n-37) +15900557729248*a(n-38) +2635188748768*a(n-39) -2803132131904*a(n-40) -102351217472*a(n-41) +284333800832*a(n-42) -15435123840*a(n-43) -12584140800*a(n-44) +1510096896*a(n-45).

Example

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

Crossrefs

Column 4 of A234443.

Sequence in context: A342876 A175340 A181928 * A060095 A343459 A282402

Adjacent sequences: A234436 A234437 A234438 * A234440 A234441 A234442

Keyword

nonn

Author

R. H. Hardin, Dec 26 2013

Status

approved