cp's OEIS Frontend

This is a front-end for the Online Encyclopedia of Integer Sequences, made by Christian Perfect. The idea is to provide OEIS entries in non-ancient HTML, and then to think about how they're presented visually. The source code is on GitHub.

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.

Original entry on oeis.org

4, 33, 228, 1561, 10648, 72625, 495329, 3378333, 23041525, 157152036, 1071837150, 7310340394, 49859324875, 340059715828, 2319337668908, 15818772327435, 107890093495975, 735851811608802, 5018791541488065, 34230082931837488
Offset: 1

Views

Author

R. H. Hardin, Dec 29 2012

Keywords

Comments

Column 3 of A221035.

Examples

			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.

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