A279300 Number of n X 1 0..2 arrays with no element equal to a strict majority of its king-move neighbors, with the exception of exactly two elements, and with new values introduced in order 0 sequentially upwards.

0, 1, 0, 3, 6, 24, 72, 232, 720, 2232, 6848, 20880, 63264, 190656, 571776, 1707264, 5077504, 15046272, 44439552, 130854656, 384228864, 1125285888, 3287672832, 9583835136, 27879174144, 80941029376, 234562535424, 678574706688

Offset

1,4

Comments

Column 1 of A279305.

Links

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

Formula

Empirical: a(n) = 6*a(n-1) - 6*a(n-2) - 16*a(n-3) + 12*a(n-4) + 24*a(n-5) + 8*a(n-6) for n>8.

Empirical g.f.: x^2*(1 - 2*x - x^2)*(1 - 4*x + 2*x^2 + 4*x^3 + 4*x^4) / (1 - 2*x - 2*x^2)^3. - Colin Barker, Feb 21 2018

Example

All solutions for n=4:
..0. .0. .0
..0. .1. .0
..1. .1. .0
..1. .1. .1

Crossrefs

Cf. A279305.

Sequence in context: A148654 A148655 A148656 * A054718 A132390 A363016

Adjacent sequences: A279297 A279298 A279299 * A279301 A279302 A279303

Keyword

nonn

Author

R. H. Hardin, Dec 09 2016

Status

approved