A234992 Number of (n+1) X (1+1) 0..6 arrays with every 2 X 2 subblock having its diagonal sum differing from its antidiagonal sum by 2, with no adjacent elements equal (constant-stress tilted 1 X 1 tilings).

172, 916, 5280, 31944, 196148, 1214044, 7532324, 46791008, 290776568, 1807339968, 11234293404, 69833627132, 434097609572, 2698436446136, 16774037447840, 104270950787408, 648170340713028, 4029164730233420, 25046145986188500

Offset

1,1

Comments

Column 1 of A234998.

Links

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

Formula

Empirical: a(n) = 5*a(n-1) +21*a(n-2) -70*a(n-3) -144*a(n-4) +326*a(n-5) +381*a(n-6) -549*a(n-7) -351*a(n-8) +198*a(n-9) +54*a(n-10).

Example

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

Crossrefs

Column 1 of A234998.

Sequence in context: A246475 A202641 A234998 * A213992 A214115 A250968

Adjacent sequences: A234989 A234990 A234991 * A234993 A234994 A234995

Keyword

nonn

Author

R. H. Hardin, Jan 02 2014

Status

approved