A229368 Number of nX4 0..2 arrays avoiding 11 horizontally, 22 vertically and 00 antidiagonally.

60, 869, 13937, 222990, 3576912, 56939585, 911301584, 14532090528, 232232172607, 3706745079815, 59203178820148, 945256319974208, 15094878048962231, 241030410158025724, 3848864771555252792, 61458856647843842612

Offset: 1

Author

R. H. Hardin Sep 21 2013

Keywords

• nonn

Comments

Column 4 of A229372

Examples

			Some solutions for n=3
..1..0..1..2....0..2..1..2....1..2..0..2....0..1..0..1....1..2..1..2
..1..0..0..1....0..1..0..1....0..1..2..0....0..1..2..2....2..0..1..0
..2..2..2..1....0..2..1..2....0..2..1..2....2..2..1..0....1..0..2..2
		

Links

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

Formula

Empirical: a(n) = 2*a(n-1) +257*a(n-2) +433*a(n-3) -16073*a(n-4) -20963*a(n-5) +481391*a(n-6) +119200*a(n-7) -7182420*a(n-8) +4731824*a(n-9) [phone]*a(n-10) -29900281*a(n-11) -162825007*a(n-12) [phone]*a(n-13) [phone]*a(n-14) [phone]*a(n-15) -378171592*a(n-16) -303446432*a(n-17) [phone]*a(n-18) [phone]*a(n-19) +6923904*a(n-20) -10505152*a(n-21) -433920*a(n-22) +664576*a(n-23) -65536*a(n-24) for n>25