A269507 Number of 3Xn arrays containing n copies of 0..3-1 avoiding the pattern down-up in every row and column.
4, 54, 420, 3088, 25226, 239994, 2338286, 23240168, 232006814, 2352889414, 24069853302, 248560741574, 2582277394354, 26997628173380, 283652378887212, 2994183763030920, 31727834772912212, 337396544704648686
Offset: 1
Keywords
Examples
Some solutions for n=4 ..1..1..2..0. .1..0..0..1. .0..0..2..1. .0..0..2..2. .0..1..2..1 ..1..1..2..2. .2..1..1..2. .0..2..2..1. .1..2..1..1. .0..2..2..1 ..0..0..0..2. .0..2..2..0. .2..1..1..0. .1..2..0..0. .2..0..0..1
Links
- R. H. Hardin, Table of n, a(n) for n = 1..48
Crossrefs
Cf. A269505.
Comments