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A250588 Number of (n+1)X(4+1) 0..2 arrays with nondecreasing max(x(i,j),x(i,j-1)) in the i direction and nondecreasing min(x(i,j),x(i-1,j)) in the j direction. 2
2375, 14983, 79415, 379397, 1686514, 7120483, 29029369, 115191907, 448833569, 1723204432, 6551633555, 24709506002, 92716016604, 346413672235, 1291010570063, 4801025640575, 17833372282529, 66175132547455 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,1

COMMENTS

Column 4 of A250592.

Appears to satisfy the same recurrence relation as A250636.

LINKS

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

FORMULA

Empirical: a(n) = 17*a(n-1) -101*a(n-2) +110*a(n-3) +1466*a(n-4) -6607*a(n-5) +2715*a(n-6) +50990*a(n-7) -125338*a(n-8) -69069*a(n-9) +724777*a(n-10) -770521*a(n-11) -1528585*a(n-12) +4147071*a(n-13) -616996*a(n-14) -8587972*a(n-15) +9209705*a(n-16) +6258473*a(n-17) -18241543*a(n-18) +5925196*a(n-19) +15364973*a(n-20) -15498239*a(n-21) -2690737*a(n-22) +12025570*a(n-23) -4880027*a(n-24) -3407185*a(n-25) +3581843*a(n-26) -420145*a(n-27) -810850*a(n-28) +400975*a(n-29) -4790*a(n-30) -48700*a(n-31) +15025*a(n-32) -1500*a(n-33) for n > 35.

EXAMPLE

Some solutions for n=3:

..1..0..0..0..1....1..0..0..0..0....0..0..2..1..1....0..0..1..1..2

..0..1..1..1..1....0..1..1..1..2....0..2..1..2..1....0..0..1..1..2

..1..0..1..2..2....2..2..2..2..2....2..0..2..1..2....0..1..2..2..2

..0..2..2..1..2....2..2..2..2..2....0..2..0..2..1....2..1..2..2..2

CROSSREFS

Column 4 of A250592.

See also A250636.

Sequence in context: A241933 A045303 A165245 * A165948 A183599 A226000

Adjacent sequences:  A250585 A250586 A250587 * A250589 A250590 A250591

KEYWORD

nonn

AUTHOR

R. H. Hardin, Nov 25 2014

STATUS

approved

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Last modified September 26 12:36 EDT 2021. Contains 347665 sequences. (Running on oeis4.)