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A221449 Hilltop maps: number of 4Xn binary arrays indicating the locations of corresponding elements not exceeded by any horizontal or antidiagonal neighbor in a random 0..1 4Xn array 1
1, 105, 1473, 18393, 260557, 3669101, 51186449, 715191073, 9997750841, 139736151537, 1953034926537, 27297122633073, 381525299372673, 5332483219348113, 74530789226270781, 1041698296419651789 (list; graph; refs; listen; history; text; internal format)
OFFSET
1,2
COMMENTS
Row 4 of A221446
LINKS
FORMULA
Empirical: a(n) = 9*a(n-1) +33*a(n-2) +415*a(n-3) +1016*a(n-4) +4212*a(n-5) +4364*a(n-6) +6084*a(n-7) -16154*a(n-8) -52326*a(n-9) -58320*a(n-10) -23560*a(n-11) +258118*a(n-12) +206162*a(n-13) -324408*a(n-14) -244116*a(n-15) +148795*a(n-16) +166349*a(n-17) -20171*a(n-18) -24653*a(n-19) -40309*a(n-20) +12497*a(n-21) -8027*a(n-22) +28179*a(n-23) -16900*a(n-24) -1964*a(n-25) -8214*a(n-26) +1038*a(n-27) -2120*a(n-28) +2536*a(n-29) +134*a(n-30) +830*a(n-31) +228*a(n-32) +188*a(n-33) +16*a(n-34) +40*a(n-35) -a(n-36) +a(n-37) +a(n-38) -a(n-39)
EXAMPLE
Some solutions for n=3
..1..1..0....1..1..1....1..1..0....0..1..1....1..0..0....0..1..1....0..1..0
..1..1..1....0..1..0....1..0..1....0..1..0....0..1..0....1..1..0....0..0..0
..1..0..1....0..0..0....0..1..0....1..0..1....0..1..0....0..0..0....1..1..1
..1..1..1....1..1..1....0..0..1....1..1..0....0..0..1....1..1..0....0..1..0
CROSSREFS
Sequence in context: A297800 A165382 A051015 * A076377 A165374 A024198
KEYWORD
nonn
AUTHOR
R. H. Hardin Jan 17 2013
STATUS
approved

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Last modified June 21 11:14 EDT 2024. Contains 373544 sequences. (Running on oeis4.)