

A280155


Number of nX2 0..1 arrays with no element unequal to a strict majority of its horizontal, vertical and antidiagonal neighbors, with the exception of exactly one element, and with new values introduced in order 0 sequentially upwards.


1



0, 4, 8, 18, 40, 92, 208, 470, 1060, 2384, 5352, 11992, 26824, 59906, 133592, 297510, 661720, 1470062, 3262264, 7231940, 16016596, 35439722, 78349800, 173074816, 382029988, 842648168, 1857362384, 4091321478, 9006604780, 19815365450
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OFFSET

1,2


COMMENTS

Column 2 of A280161.


LINKS

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


FORMULA

Empirical: a(n) = 2*a(n1) +3*a(n2) 2*a(n3) 6*a(n4) 4*a(n5) a(n6) for n>8


EXAMPLE

Some solutions for n=4
..0..0. .0..0. .0..0. .0..0. .0..0. .0..0. .0..0. .0..0. .0..0. .0..1
..0..0. .0..0. .0..1. .0..0. .0..1. .1..0. .0..0. .0..1. .1..1. .0..0
..1..1. .1..0. .1..1. .0..0. .0..0. .0..0. .0..0. .1..1. .1..0. .0..1
..1..0. .0..0. .0..0. .0..1. .0..0. .0..0. .1..1. .1..0. .0..0. .1..1


CROSSREFS

Cf. A280161.
Sequence in context: A228231 A175657 A080287 * A075310 A075797 A104137
Adjacent sequences: A280152 A280153 A280154 * A280156 A280157 A280158


KEYWORD

nonn


AUTHOR

R. H. Hardin, Dec 27 2016


STATUS

approved



