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A281716
Number of 2 X n 0..1 arrays with no element unequal to a strict majority of its horizontal, diagonal and antidiagonal neighbors and with new values introduced in order 0 sequentially upwards.
1
2, 3, 7, 14, 29, 61, 126, 265, 553, 1162, 2441, 5141, 10846, 22921, 48529, 102914, 218617, 465133, 991158, 2115193, 4520361, 9673530, 20728009, 44469637, 95515790, 205383337, 442086081, 952519602, 2054191833, 4433875101, 9578060710
OFFSET
1,1
LINKS
FORMULA
Empirical: a(n) = 3*a(n-1) + a(n-2) - 6*a(n-3) - 2*a(n-4) + 4*a(n-5).
Empirical g.f.: x*(2 - 3*x - 4*x^2 + 2*x^3 + 2*x^4) / ((1 - 2*x)*(1 - x - 3*x^2 + 2*x^4)). - Colin Barker, Feb 20 2019
EXAMPLE
Some solutions for n=4:
..0..0..1..1. .0..0..1..0. .0..1..1..1. .0..1..1..0. .0..1..0..0
..0..1..1..1. .1..1..0..1. .1..0..0..0. .1..0..0..1. .1..0..1..1
CROSSREFS
Row 2 of A281715.
Sequence in context: A135258 A034065 A034075 * A192570 A019595 A112884
KEYWORD
nonn
AUTHOR
R. H. Hardin, Jan 28 2017
STATUS
approved