A235193 Number of (n+1) X (3+1) 0..6 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).

1880, 4724, 12176, 35868, 105208, 333340, 1043256, 3446068, 11230320, 38241780, 128423464, 448265876, 1541798936, 5493045164, 19259557328, 69772185756, 248380454616, 911885089884, 3284787994840, 12186209514644, 44296484322480

Offset

1,1

Links

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

Formula

Empirical: a(n) = 9*a(n-1) +57*a(n-2) -731*a(n-3) -878*a(n-4) +26304*a(n-5) -15900*a(n-6) -552844*a(n-7) +899723*a(n-8) +7521105*a(n-9) -18125633*a(n-10) -69122561*a(n-11) +220983779*a(n-12) +431291855*a(n-13) -1831340243*a(n-14) -1746606119*a(n-15) +10803108780*a(n-16) +3716404250*a(n-17) -46315168788*a(n-18) +2550194940*a(n-19) +145490417695*a(n-20) -46954531755*a(n-21) -335197745077*a(n-22) +166429786799*a(n-23) +564880422518*a(n-24) -334400168840*a(n-25) -694120308016*a(n-26) +424547635156*a(n-27) +620744392928*a(n-28) -343613520080*a(n-29) -401608244880*a(n-30) +170947437904*a(n-31) +182786646240*a(n-32) -46865973504*a(n-33) -54609655680*a(n-34) +4665398976*a(n-35) +9369063936*a(n-36) +551978496*a(n-37) -679311360*a(n-38) -113218560*a(n-39).

Example

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

Crossrefs

Column 3 of A235198.

Sequence in context: A020407 A320719 A358147 * A072494 A260137 A246478

Adjacent sequences: A235190 A235191 A235192 * A235194 A235195 A235196

Keyword

nonn

Author

R. H. Hardin, Jan 04 2014

Status

approved