A234675 Number of (n+1) X (2+1) 0..5 arrays with every 2 X 2 subblock having its diagonal sum differing from its antidiagonal sum by 5 (constant-stress 1 X 1 tilings).

404, 1152, 2924, 9108, 25292, 82956, 243164, 823836, 2495084, 8636892, 26700764, 93812028, 294012332, 1044061596, 3303828764, 11823983676, 37682184044, 135642577692, 434618272604, 1571271439548, 5055647094572, 18337480193436

Offset

1,1

Links

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

Formula

Empirical: a(n) = 4*a(n-1) +47*a(n-2) -200*a(n-3) -901*a(n-4) +4204*a(n-5) +8957*a(n-6) -48440*a(n-7) -47194*a(n-8) +334096*a(n-9) +101948*a(n-10) -1410080*a(n-11) +170136*a(n-12) +3549696*a(n-13) -1446912*a(n-14) -4861440*a(n-15) +2954880*a(n-16) +2764800*a(n-17) -2073600*a(n-18).

Example

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

Crossrefs

Column 2 of A234681.

Sequence in context: A117836 A185640 A185637 * A135791 A187382 A306308

Adjacent sequences: A234672 A234673 A234674 * A234676 A234677 A234678

Keyword

nonn

Author

R. H. Hardin, Dec 29 2013

Status

approved