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A208079 revision #5

A208079

Number of 4Xn 0..1 arrays avoiding 0 0 0 and 0 0 1 horizontally and 0 0 0 and 0 1 0 vertically

9, 81, 441, 2601, 15129, 88209, 514089, 2996361, 17464041, 101787921, 593263449, 3457792809, 20153493369, 117463167441, 684625511241, 3990289900041, 23257113888969, 135552393433809, 790057246713849, 4604791086849321

(list; graph; refs; listen; history; text; internal format)

OFFSET

1,1

COMMENTS

Row 4 of A208078

LINKS

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

FORMULA

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

EXAMPLE

Some solutions for n=4

..1..0..1..0....1..1..0..1....1..1..1..1....0..1..1..0....1..1..1..0