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A219811 Number of nX3 arrays of the minimum value of corresponding elements and their horizontal, vertical or diagonal neighbors in a random, but sorted with lexicographically nondecreasing rows and nonincreasing columns, 0..2 nX3 array 1
6, 15, 62, 169, 414, 987, 2359, 5569, 12737, 27982, 59028, 119947, 235727, 449688, 835225, 1513962, 2683186, 4656429, 7922316, 13228338, 21698084, 34992721, 55530195, 86778791, 133645391, 202983064, 304247572, 450338045, 658663533 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,1

COMMENTS

Column 3 of A219816

LINKS

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

FORMULA

Empirical: a(n) = (1/13305600)*n^11 - (1/725760)*n^10 + (1/51840)*n^9 + (1/6048)*n^8 - (5437/1209600)*n^7 + (2519/34560)*n^6 - (1003/3024)*n^5 - (47861/72576)*n^4 + (820873/64800)*n^3 - (230969/10080)*n^2 - (577453/27720)*n + 76 for n>4

EXAMPLE

Some solutions for n=3

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

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

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

CROSSREFS

Sequence in context: A067665 A012595 A012294 * A255007 A069750 A233450

Adjacent sequences:  A219808 A219809 A219810 * A219812 A219813 A219814

KEYWORD

nonn

AUTHOR

R. H. Hardin Nov 28 2012

STATUS

approved

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Last modified March 30 06:59 EDT 2020. Contains 333119 sequences. (Running on oeis4.)