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A219933 Number of nX2 arrays of the minimum value of corresponding elements and their horizontal or diagonal neighbors in a random, but sorted with lexicographically nondecreasing rows and nonincreasing columns, 0..3 nX2 array 1
4, 23, 76, 208, 519, 1212, 2670, 5574, 11076, 21043, 38390, 67522, 114907, 189804, 305172, 478788, 734604, 1104375, 1629592, 2363756, 3375031, 4749316, 6593778, 9040890, 12253020, 16427619, 21803058, 28665166, 37354523, 48274564, 61900552 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,1

COMMENTS

Column 2 of A219939

LINKS

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

FORMULA

Empirical: a(n) = (1/20160)*n^8 + (1/1680)*n^7 + (1/1440)*n^6 + (23/240)*n^5 - (613/2880)*n^4 + (211/120)*n^3 + (11149/5040)*n^2 + (61/420)*n

EXAMPLE

Some solutions for n=3

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

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

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

CROSSREFS

Sequence in context: A226411 A226342 A071246 * A304305 A316204 A305771

Adjacent sequences:  A219930 A219931 A219932 * A219934 A219935 A219936

KEYWORD

nonn

AUTHOR

R. H. Hardin Dec 01 2012

STATUS

approved

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Last modified July 6 15:57 EDT 2022. Contains 355111 sequences. (Running on oeis4.)