A221030 Majority value maps: number of n X 3 binary arrays indicating the locations of corresponding elements equal to at least half of their horizontal and antidiagonal neighbors in a random 0..2 n X 3 array.

4, 33, 228, 1561, 10648, 72625, 495329, 3378333, 23041525, 157152036, 1071837150, 7310340394, 49859324875, 340059715828, 2319337668908, 15818772327435, 107890093495975, 735851811608802, 5018791541488065, 34230082931837488

Offset

1,1

Comments

Column 3 of A221035.

Links

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

Formula

Empirical: a(n) = 8*a(n-1) - 8*a(n-2) - a(n-3) + 5*a(n-4) - 2*a(n-5).

Empirical g.f.: x*(4 + x - 4*x^2 + 5*x^3 - 3*x^4) / (1 - 8*x + 8*x^2 + x^3 - 5*x^4 + 2*x^5). - Colin Barker, Mar 13 2018

Example

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

Crossrefs

Cf. A221035.

Sequence in context: A273708 A097705 A131509 * A081007 A213168 A203212

Adjacent sequences: A221027 A221028 A221029 * A221031 A221032 A221033

Keyword

nonn

Author

R. H. Hardin, Dec 29 2012

Status

approved