A268015 Number of nX3 0..2 arrays with every repeated value in every row and column greater than or equal to the previous repeated value.

27, 729, 19683, 474552, 10941048, 240641848, 5106219048, 105087226959, 2107490863661, 41332013859375, 794974954718853, 15030454569975872, 279880270014528000, 5140991504979000000, 93278442949595408448

Offset

1,1

Comments

Column 3 of A268019.

Links

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

Formula

Empirical: a(n) = 84*a(n-1) -2814*a(n-2) +45276*a(n-3) -285019*a(n-4) -1063944*a(n-5) +20124468*a(n-6) -1605816*a(n-7) -630123753*a(n-8) -402925572*a(n-9) +10392502302*a(n-10) +30566899188*a(n-11) +12457260613*a(n-12) -49186967088*a(n-13) -30986023080*a(n-14) +49186967088*a(n-15) +12457260613*a(n-16) -30566899188*a(n-17) +10392502302*a(n-18) +402925572*a(n-19) -630123753*a(n-20) +1605816*a(n-21) +20124468*a(n-22) +1063944*a(n-23) -285019*a(n-24) -45276*a(n-25) -2814*a(n-26) -84*a(n-27) -a(n-28)

Example

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

Crossrefs

Cf. A268019.

Sequence in context: A228973 A171301 A098838 * A009971 A373218 A307388

Adjacent sequences: A268012 A268013 A268014 * A268016 A268017 A268018

Keyword

nonn

Author

R. H. Hardin, Jan 24 2016

Status

approved