A279575 Number of n X 3 0..2 arrays with no element equal to a strict majority of its horizontal and antidiagonal neighbors, with the exception of exactly one element, and with new values introduced in order 0 sequentially upwards.

2, 36, 944, 23072, 547168, 12701248, 290067328, 6540226304, 145949741056, 3229393518592, 70948621604864, 1549301789257728, 33656105642434560, 727817498719862784, 15676632552910815232, 336475872266838999040

Offset

1,1

Links

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

Formula

Empirical: a(n) = 44*a(n-1) - 556*a(n-2) + 1616*a(n-3) - 2000*a(n-4) + 1152*a(n-5) - 256*a(n-6) for n>7.

Empirical g.f.: 2*x*(1 - 2*x)^2*(1 - 22*x + 144*x^2 - 176*x^3 + 64*x^4) / (1 - 22*x + 36*x^2 - 16*x^3)^2. - Colin Barker, Feb 11 2019

Example

Some solutions for n=4:
..0..0..1. .0..1..2. .0..1..2. .0..1..2. .0..0..1. .0..1..1. .0..0..1
..2..0..0. .1..1..0. .2..1..2. .1..0..2. .1..1..0. .2..2..1. .2..1..0
..1..1..0. .2..1..1. .1..0..1. .2..1..1. .0..1..2. .0..2..0. .2..2..2
..0..1..0. .2..0..2. .0..2..2. .1..2..2. .2..1..2. .2..2..1. .0..1..0

Crossrefs

Column 3 of A279580.

Sequence in context: A093530 A001626 A166473 * A009539 A009554 A209036

Adjacent sequences: A279572 A279573 A279574 * A279576 A279577 A279578

Keyword

nonn

Author

R. H. Hardin, Dec 15 2016

Status

approved