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A207431 Number of 7Xn 0..1 arrays avoiding 0 0 0 and 0 1 0 horizontally and 0 0 1 and 0 1 0 vertically 1
31, 961, 11067, 127449, 2048823, 32936121, 474552171, 6837470721, 102807481767, 1545802349809, 22864149458035, 338186399124025, 5035128104126565, 74966098845588129, 1113208750837622133, 16530588386278151641 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,1

COMMENTS

Row 7 of A207426

LINKS

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

EXAMPLE

Some solutions for n=4

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

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

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

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

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

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

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

CROSSREFS

Sequence in context: A207247 A208168 A207441 * A208373 A171305 A009975

Adjacent sequences:  A207428 A207429 A207430 * A207432 A207433 A207434

KEYWORD

nonn

AUTHOR

R. H. Hardin Feb 17 2012

STATUS

approved

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Last modified April 3 17:03 EDT 2020. Contains 333197 sequences. (Running on oeis4.)