A234551 Number of (n+1) X (2+1) 0..6 arrays with every 2 X 2 subblock having its diagonal sum differing from its antidiagonal sum by 3 (constant-stress 1 X 1 tilings).

2716, 22458, 184816, 1527660, 12632704, 104793676, 870061872, 7247511972, 60427123392, 505598378732, 4234359329552, 35597000634596, 299528022187872, 2530562921714700, 21397823598521904, 181712718030164164

Offset

1,1

Links

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

Formula

Empirical: a(n) = 25*a(n-1) +171*a(n-2) -8947*a(n-3) +20442*a(n-4) +1276046*a(n-5) -7721142*a(n-6) -89665378*a(n-7) +835291375*a(n-8) +2916848953*a(n-9) -45270570765*a(n-10) -12096348459*a(n-11) +1332333947744*a(n-12) -1813960758728*a(n-13) -21440506572936*a(n-14) +48154351857440*a(n-15) +200413362270168*a(n-16) -574094316035800*a(n-17) -1131202886847072*a(n-18) +3914657325465440*a(n-19) +3861853479350272*a(n-20) -16494937667180864*a(n-21) -7509328290739200*a(n-22) +44239728068980992*a(n-23) +6116716146439680*a(n-24) -75931240737844224*a(n-25) +4864198828197888*a(n-26) +81940531841003520*a(n-27) -16357767821991936*a(n-28) -52834812420096000*a(n-29) +15489875939328000*a(n-30) +18143005999104000*a(n-31) -6490659697459200*a(n-32) -2459495301120000*a(n-33) +983798120448000*a(n-34).

Example

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

Crossrefs

Column 2 of A234555.

Sequence in context: A205472 A252430 A031622 * A167836 A290644 A231289

Adjacent sequences: A234548 A234549 A234550 * A234552 A234553 A234554

Keyword

nonn

Author

R. H. Hardin, Dec 28 2013

Status

approved