login

Year-end appeal: Please make a donation to the OEIS Foundation to support ongoing development and maintenance of the OEIS. We are now in our 61st year, we have over 378,000 sequences, and we’ve reached 11,000 citations (which often say “discovered thanks to the OEIS”).

A218586
Hilltop maps: number of n X n binary arrays indicating the locations of corresponding elements not exceeded by any horizontal or antidiagonal neighbor in a random 0..2 n X n array
1
1, 13, 449, 56629, 28543403, 57707873919, 467122877883141, 15124271280844676313, 1958173356335852318774549, 1013875932726564267833657180687
OFFSET
1,2
COMMENTS
Diagonal of A218592
EXAMPLE
Some solutions for n=3
..1..1..0....1..1..0....0..0..1....0..1..0....1..0..0....1..0..0....1..0..1
..1..0..1....0..0..1....0..0..1....1..1..0....0..1..1....1..0..0....1..0..1
..0..1..1....1..0..0....0..0..0....1..1..0....1..0..1....0..1..0....1..1..1
CROSSREFS
Sequence in context: A372812 A012832 A102075 * A251601 A338177 A166184
KEYWORD
nonn
AUTHOR
R. H. Hardin Nov 03 2012
STATUS
approved