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A218206 T(n,k)=Hilltop maps: number of nXk binary arrays indicating the locations of corresponding elements not exceeded by any horizontal or vertical neighbor in a random 0..2 nXk array 9
1, 3, 3, 7, 15, 7, 13, 59, 59, 13, 25, 233, 483, 233, 25, 49, 929, 3841, 3841, 929, 49, 97, 3697, 30599, 61013, 30599, 3697, 97, 191, 14719, 243953, 971849, 971849, 243953, 14719, 191, 375, 58599, 1945103, 15491481, 30954777, 15491481, 1945103, 58599 (list; table; graph; refs; listen; history; text; internal format)
OFFSET

1,2

COMMENTS

Table starts

....1........3...........7.............13...............25................49

....3.......15..........59............233..............929..............3697

....7.......59.........483...........3841............30599............243953

...13......233........3841..........61013...........971849..........15491481

...25......929.......30599.........971849.........30954777.........986715373

...49.....3697......243953.......15491481........986715373.......62898202889

...97....14719.....1945103......246985085......31459153095.....4010296932181

..191....58599....15508803.....3937780585....1003007190421...255691410570153

..375...233291...123654745....62780737565...31978263226027.16302319940388693

..737...928769...985923281..1000923719573.1019542444050089

.1449..3697573..7860958915.15957894038581

.2849.14720617.62676962321

LINKS

R. H. Hardin, Table of n, a(n) for n = 1..112

FORMULA

Empirical: Column k=1 for an underlying 0..z array: a(n) = sum(i=1..2z+1){a(n-i)} z=1,2,3,4

EXAMPLE

Some solutions for n=3 k=4

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

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

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

CROSSREFS

Column 1 is A218199, see also A102026

Sequence in context: A049772 A119470 A060368 * A218233 A218319 A218196

Adjacent sequences:  A218203 A218204 A218205 * A218207 A218208 A218209

KEYWORD

nonn,tabl

AUTHOR

R. H. Hardin Oct 23 2012

STATUS

approved

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Last modified December 5 15:06 EST 2021. Contains 349557 sequences. (Running on oeis4.)