A220381 - OEIS

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A220381

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..1 n X 3 array.

4, 25, 136, 753, 4160, 22989, 127037, 702009, 3879313, 21437148, 118462034, 654623158, 3617458391, 19990134860, 110465815644, 610435923087, 3373279000591, 18640795512630, 103009344107857, 569231338133692

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OFFSET

1,1

COMMENTS

Column 3 of A220386.

LINKS

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

FORMULA

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

Empirical g.f.: x*(4 + 9*x + 4*x^2 - 3*x^3 - 3*x^4) / (1 - 4*x - 8*x^2 - 3*x^3 + 3*x^4 + 2*x^5). - Colin Barker, Jul 31 2018

EXAMPLE

Some solutions for n=3: