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A279705
Number of n X 4 0..1 arrays with no element equal to a strict majority of its horizontal and antidiagonal neighbors and with new values introduced in order 0 sequentially upwards.
1
2, 4, 22, 125, 717, 4121, 23690, 136181, 782826, 4500021, 25868076, 148700951, 854797731, 4913749086, 28246366671, 162372399730, 933387168180, 5365515365948, 30843315747327, 177300792451846, 1019202061854748
OFFSET
1,1
LINKS
FORMULA
Empirical: a(n) = 10*a(n-1) - 33*a(n-2) + 61*a(n-3) - 78*a(n-4) + 64*a(n-5) - 32*a(n-6) + 9*a(n-7) - a(n-8) for n>9.
Empirical g.f.: x*(2 - 16*x + 48*x^2 - 85*x^3 + 105*x^4 - 82*x^5 + 40*x^6 - 11*x^7 + x^8) / (1 - 10*x + 33*x^2 - 61*x^3 + 78*x^4 - 64*x^5 + 32*x^6 - 9*x^7 + x^8). - Colin Barker, Feb 11 2019
EXAMPLE
Some solutions for n=4:
..0..1..0..1. .0..1..0..1. .0..1..0..0. .0..1..0..1. .0..1..0..1
..1..0..1..1. .0..0..1..1. .0..1..1..0. .1..0..0..1. .0..0..1..1
..1..0..0..1. .1..0..0..0. .0..0..1..1. .1..1..0..1. .1..0..0..1
..1..0..1..0. .0..1..1..0. .0..1..0..1. .0..1..0..1. .0..1..0..1
CROSSREFS
Column 4 of A279709.
Sequence in context: A165588 A289191 A235938 * A321248 A309741 A110130
KEYWORD
nonn
AUTHOR
R. H. Hardin, Dec 17 2016
STATUS
approved