A208707 Number of n X 6 0..1 arrays with new values 0..1 introduced in row major order and no element equal to more than two of its immediate leftward or upward or right-upward antidiagonal neighbors.

32, 1268, 52184, 2142580, 87985748, 3613193828, 148378294612, 6093257064980, 250223806647572, 10275613313012692, 421975152458430164, 17328700863708613076, 711615060447141699796, 29222963581518749645012

Offset: 1

Author

R. H. Hardin, Mar 01 2012

Keywords

• nonn

Comments

Column 6 of A208709.

Examples

			Some solutions for n=4:
..0..0..1..0..1..1....0..0..0..0..0..1....0..0..0..1..0..1....0..0..0..1..0..0
..0..0..0..0..1..0....1..0..1..0..1..1....1..0..1..1..0..1....0..1..1..0..1..1
..1..0..1..0..0..1....1..1..1..1..0..1....0..0..1..0..1..1....0..1..0..0..0..1
..1..0..1..0..1..0....0..1..0..0..1..0....1..0..0..1..0..0....0..1..1..0..1..0
		

Links

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

Crossrefs

Cf. A208709.

Formula

Empirical: a(n) = 45*a(n-1) - 168*a(n-2) + 272*a(n-3) - 324*a(n-4) + 240*a(n-5) - 64*a(n-6) for n>7.

Empirical g.f.: 4*x*(8 - 43*x + 125*x^2 - 345*x^3 + 508*x^4 - 572*x^5 + 400*x^6) / ((1 - x)*(1 - 44*x + 124*x^2 - 148*x^3 + 176*x^4 - 64*x^5)). - Colin Barker, Jul 06 2018