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A250988
Number of (n+1)X(2+1) 0..2 arrays with nondecreasing min(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
1
169, 872, 4111, 18387, 80133, 344135, 1466191, 6219851, 26329263, 111352239, 470824467, 1991012259, 8422006891, 35637583483, 150851830807, 638746833775, 2705353300919, 11460847050775, 48561125420483, 205789941962155
OFFSET
1,1
COMMENTS
Column 2 of A250994
LINKS
FORMULA
Empirical: a(n) = 14*a(n-1) -73*a(n-2) +156*a(n-3) -13*a(n-4) -480*a(n-5) +581*a(n-6) +212*a(n-7) -654*a(n-8) +78*a(n-9) +264*a(n-10) -44*a(n-11) -40*a(n-12)
EXAMPLE
Some solutions for n=4
..0..2..0....0..0..2....1..0..1....1..0..2....2..0..2....0..0..2....0..1..1
..0..0..2....1..2..0....1..0..2....1..0..2....2..0..1....0..0..2....0..1..2
..1..1..0....1..2..0....0..2..0....0..2..0....2..0..2....0..0..1....1..2..1
..1..1..1....1..1..1....2..0..2....1..1..1....1..1..1....0..1..0....1..1..2
..2..2..2....2..2..2....2..1..1....1..1..2....1..1..2....0..0..1....1..1..1
CROSSREFS
Sequence in context: A017534 A120904 A038596 * A289338 A256979 A293477
KEYWORD
nonn
AUTHOR
R. H. Hardin, Nov 29 2014
STATUS
approved