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A218350 Hilltop maps: number of nX4 binary arrays indicating the locations of corresponding elements not exceeded by any horizontal or vertical neighbor in a random 0..1 nX4 array 2
9, 149, 2069, 28661, 401253, 5609569, 78394141, 1095695529, 15314367301, 214044940145, 2991651891557, 41813576818545, 584417958076589, 8168264238929833, 114165795446827469, 1595666897305379897 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,1

COMMENTS

Column 4 of A218354

LINKS

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

FORMULA

Empirical: a(n) = 10*a(n-1) +36*a(n-2) +242*a(n-3) +413*a(n-4) +482*a(n-5) -720*a(n-6) -2212*a(n-7) -683*a(n-8) +466*a(n-9) +121*a(n-10) -414*a(n-11) -119*a(n-12) -100*a(n-13) +241*a(n-14) +36*a(n-15) +164*a(n-16) -44*a(n-17) +35*a(n-18) -4*a(n-19) +2*a(n-20) +2*a(n-21) -a(n-22)

EXAMPLE

Some solutions for n=3

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

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

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

CROSSREFS

Sequence in context: A266128 A183439 A296017 * A337672 A027018 A326012

Adjacent sequences:  A218347 A218348 A218349 * A218351 A218352 A218353

KEYWORD

nonn

AUTHOR

R. H. Hardin Oct 26 2012

STATUS

approved

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Last modified December 1 10:54 EST 2021. Contains 349428 sequences. (Running on oeis4.)