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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
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
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
KEYWORD
nonn
AUTHOR
R. H. Hardin, Dec 10 2012
STATUS
approved