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

1,1

Comments

Column 4 of A229372

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) +44618241*a(n-10) -29900281*a(n-11) -162825007*a(n-12) +45010518*a(n-13) +361117327*a(n-14) +96538808*a(n-15) -378171592*a(n-16) -303446432*a(n-17) +22354064*a(n-18) +83608448*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

Example

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

Crossrefs

Sequence in context: A008357 A259539 A138898 * A305625 A056321 A056312

Adjacent sequences: A229365 A229366 A229367 * A229369 A229370 A229371

Keyword

nonn

Author

R. H. Hardin Sep 21 2013

Status

approved