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A218642 Hilltop maps: number of 7Xn binary arrays indicating the locations of corresponding elements not exceeded by any horizontal, diagonal or antidiagonal neighbor in a random 0..3 7Xn array 0
1, 16001, 2092027, 268378101, 34351677143, 4396930705721, 562806164441653, 72039176523059285 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,2

COMMENTS

Row 7 of A218638

LINKS

Table of n, a(n) for n=1..8.

EXAMPLE

Some solutions for n=3

..0..0..0....0..0..0....0..0..0....0..0..0....0..0..0....0..0..0....0..0..0

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

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

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

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

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

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

CROSSREFS

Sequence in context: A251848 A129473 A237681 * A151811 A151877 A187854

Adjacent sequences:  A218639 A218640 A218641 * A218643 A218644 A218645

KEYWORD

nonn

AUTHOR

R. H. Hardin Nov 03 2012

STATUS

approved

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Last modified December 5 09:45 EST 2021. Contains 349543 sequences. (Running on oeis4.)