A183426 Half the number of n X 3 0..2 arrays with no element equal its row sum plus its column sum mod 3.

9, 32, 256, 2097, 16384, 131072, 1048959, 8388608, 67108864, 536873985, 4294967296, 34359738368, 274877931519, 2199023255552, 17592186044416, 140737488551937, 1125899906842624, 9007199254740992, 72057594039500799

Offset

1,1

Comments

Column 3 of A183429.

Links

R. H. Hardin, Table of n, a(n) for n = 1..161

Formula

Empirical: a(n) = 8*a(n-1) + 7*a(n-3) - 56*a(n-4) + 8*a(n-6) - 64*a(n-7).

Empirical g.f.: x*(9 - 40*x - 14*x^3 - 112*x^4 - 32*x^6) / ((1 + x)*(1 - 2*x)*(1 - 8*x)*(1 - x + x^2)*(1 + 2*x + 4*x^2)). - Colin Barker, Mar 29 2018

Example

Some solutions for 4X3
..1..1..2....0..2..1....2..2..2....2..2..2....2..2..1....0..0..2....2..1..0
..1..0..1....1..0..0....1..0..0....0..1..1....1..2..1....1..2..0....2..1..1
..0..2..2....0..2..0....0..1..2....1..1..1....2..2..1....1..0..0....1..0..1
..2..2..1....1..0..2....1..0..0....0..2..2....2..2..1....0..1..2....1..0..2

Crossrefs

Cf. A183429.

Sequence in context: A300773 A317279 A196016 * A061913 A264512 A231764

Adjacent sequences: A183423 A183424 A183425 * A183427 A183428 A183429

Keyword

nonn

Author

R. H. Hardin, Jan 04 2011

Status

approved