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A250684 Number of (n+1)X(n+1) 0..3 arrays with nondecreasing x(i,j)-x(i,j-1) in the i direction and nondecreasing absolute value of x(i,j)-x(i-1,j) in the j direction 0
104, 2920, 74631, 1670016, 31728758, 523260542, 7662909389 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,1

COMMENTS

Diagonal of A250691

LINKS

Table of n, a(n) for n=1..7.

EXAMPLE

Some solutions for n=3

..3..2..1..1....3..3..1..0....2..0..0..0....3..3..2..0....1..3..1..0

..2..1..0..0....3..3..1..0....2..0..0..0....3..3..2..2....1..3..2..1

..2..1..0..0....3..3..1..1....3..1..1..1....2..2..1..1....0..2..1..0

..1..2..3..3....2..2..0..2....2..3..3..3....1..3..3..3....0..2..1..3

CROSSREFS

Sequence in context: A298840 A298628 A281536 * A299601 A217773 A298460

Adjacent sequences:  A250681 A250682 A250683 * A250685 A250686 A250687

KEYWORD

nonn

AUTHOR

R. H. Hardin, Nov 26 2014

STATUS

approved

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Last modified November 29 21:32 EST 2021. Contains 349416 sequences. (Running on oeis4.)