A220309 Majority value maps: number of n X 2 binary arrays indicating the locations of corresponding elements equal to at least half of their horizontal, vertical and antidiagonal neighbors in a random 0..3 n X 2 array.

2, 9, 40, 155, 617, 2457, 9785, 38986, 155300, 618678, 2464607, 9818228, 39112730, 155812804, 620709233, 2472710322, 9850500300, 39241295090, 156324978076, 622749547526, 2480838338958, 9882879704522, 39370284519705, 156838831344437

Offset

1,1

Comments

Column 2 of A220313.

Links

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

Formula

Empirical: a(n) = 4*a(n-1) + 2*a(n-2) - 8*a(n-3) - 3*a(n-4) + 9*a(n-5) - 2*a(n-6) - 2*a(n-7) - a(n-8) + a(n-9) for n>10.

Empirical g.f.: x*(2 + x - 7*x^3 - 5*x^4 + 8*x^5 + 6*x^6 - 5*x^7 - 2*x^8 + x^9) / (1 - 4*x - 2*x^2 + 8*x^3 + 3*x^4 - 9*x^5 + 2*x^6 + 2*x^7 + x^8 - x^9). - Colin Barker, Mar 13 2018

Example

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

Crossrefs

Cf. A220313.

Sequence in context: A075873 A124722 A317129 * A019066 A097070 A164033

Adjacent sequences: A220306 A220307 A220308 * A220310 A220311 A220312

Keyword

nonn

Author

R. H. Hardin, Dec 10 2012

Status

approved