

A220304


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..1 n X 2 array.


1



2, 7, 26, 86, 291, 980, 3309, 11161, 37656, 127036, 428581, 1445887, 4877950, 16456589, 55519107, 187303144, 631899019, 2131818803, 7192053308, 24263615009, 81857431864, 276159968238, 931672620616, 3143156039330, 10603971469191
(list;
graph;
refs;
listen;
history;
text;
internal format)



OFFSET

1,1


COMMENTS

Column 2 of A220308.


LINKS

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


FORMULA

Empirical: a(n) = 3*a(n1) + a(n2)  a(n3) + 6*a(n4) + 3*a(n6) + 3*a(n7)  a(n8) + 3*a(n9)  a(n10).
Empirical g.f.: x*(2 + x + 3*x^2 + 3*x^3 + 2*x^4 + 5*x^5 + 2*x^6 + 2*x^7 + x^8 + x^9) / (1  3*x  x^2 + x^3  6*x^4  3*x^6  3*x^7 + x^8  3*x^9 + x^10).  Colin Barker, Jul 31 2018


EXAMPLE

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


CROSSREFS

Cf. A220308.
Sequence in context: A335179 A091145 A261332 * A300451 A212961 A000697
Adjacent sequences: A220301 A220302 A220303 * A220305 A220306 A220307


KEYWORD

nonn


AUTHOR

R. H. Hardin, Dec 10 2012


STATUS

approved



