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A229776 Number of 4X4 0..n arrays with rows in lexicographically nondecreasing order and columns in nonincreasing order 1
70, 12958, 1058494, 35452250, 637396928, 7379634620, 61734072288, 402537583863, 2155573868470, 9841145888530, 39380724254950, 141067066333648, 459822149867432, 1381730749348760, 3867950992777232, 10173948824534685 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,1

COMMENTS

Row 4 of A229774

LINKS

R. H. Hardin, Table of n, a(n) for n = 1..42

FORMULA

Empirical: a(n) = (1/5040)*n^16 + (17/5040)*n^15 + (89/3360)*n^14 + (143/1120)*n^13 + (307/720)*n^12 + (307/288)*n^11 + (64247/30240)*n^10 + (53933/15120)*n^9 + (10645/2016)*n^8 + (71609/10080)*n^7 + (44/5)*n^6 + (14447/1440)*n^5 + (8975/864)*n^4 + (20359/2160)*n^3 + (3505/504)*n^2 + (1543/420)*n + 1

EXAMPLE

Some solutions for n=3

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

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

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

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

CROSSREFS

Sequence in context: A184275 A179713 A330244 * A231054 A007100 A103157

Adjacent sequences:  A229773 A229774 A229775 * A229777 A229778 A229779

KEYWORD

nonn

AUTHOR

R. H. Hardin, Sep 29 2013

STATUS

approved

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Last modified December 4 18:08 EST 2021. Contains 349526 sequences. (Running on oeis4.)