A250869 - OEIS

A250869

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 x(i,j)+x(i-1,j) in the j direction

90, 1456, 16262, 144248, 1097986, 7500960, 47315662, 280898512, 1590567658, 8673625464, 45876777622, 236629296200, 1195160833298, 5930230507888, 28981276937886, 139784115993376, 666528024959098, 3146266602049672

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OFFSET

1,1

COMMENTS

Diagonal of A250877

LINKS

R. H. Hardin, Table of n, a(n) for n = 1..35

EXAMPLE

Some solutions for n=4

..2..2..2..2..2....2..2..2..2..2....0..0..0..0..0....2..2..2..2..2

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

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

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

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

CROSSREFS

Sequence in context: A179800 A133350 A279438 * A234983 A166817 A166799

Adjacent sequences: A250866 A250867 A250868 * A250870 A250871 A250872

KEYWORD

nonn

AUTHOR

R. H. Hardin, Nov 28 2014

STATUS

approved