A267784 Number of nX4 0..1 arrays with every repeated value in every row greater than or equal to, and in every column greater than, the previous repeated value.

15, 225, 1056, 5081, 14956, 44742, 102954, 238813, 472174, 935890, 1669256, 2973801, 4921484, 8116406, 12686802, 19733869, 29485150, 43804354, 63094592, 90326137, 126206748, 175240166, 238647082, 322974141, 430276638, 569730226

Offset: 1

Author

R. H. Hardin, Jan 20 2016

Keywords

• nonn

Comments

Column 4 of A267788.

Examples

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

Links

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

Crossrefs

Cf. A267788.

Formula

Empirical: a(n) = 2*a(n-1) +6*a(n-2) -14*a(n-3) -14*a(n-4) +42*a(n-5) +14*a(n-6) -70*a(n-7) +70*a(n-9) -14*a(n-10) -42*a(n-11) +14*a(n-12) +14*a(n-13) -6*a(n-14) -2*a(n-15) +a(n-16) for n>18