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A278802 Number of nX3 0..2 arrays with rows in nondecreasing lexicographic order and columns in nonincreasing lexicographic order. 1
10, 63, 322, 1439, 5767, 20972, 69834, 214774, 615120, 1653047, 4196501, 10123619, 23327383, 51572441, 109818385, 225997932, 450803519, 873872396, 1649976645, 3040564120, 5478446820, 9666837555, 16728604905, 28427944695, 47495149011 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,1

COMMENTS

Column 3 of A278807.

LINKS

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

FORMULA

Empirical: a(n) = (1/20922789888000)*n^16 + (1/201180672000)*n^15 + (257/1046139494400)*n^14 + (1/130636800)*n^13 + (19241/114960384000)*n^12 + (3523/1306368000)*n^11 + (241517/7315660800)*n^10 + (284771/914457600)*n^9 + (336468511/146313216000)*n^8 + (35482669/2612736000)*n^7 + (376442771/5748019200)*n^6 + (46737917/179625600)*n^5 + (361669107043/435891456000)*n^4 + (250175041/127008000)*n^3 + (375648041/121080960)*n^2 + (13891/5040)*n + 1

EXAMPLE

Some solutions for n=4

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

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

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

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

CROSSREFS

Cf. A278807.

Sequence in context: A159240 A268945 A055368 * A077616 A145885 A093953

Adjacent sequences:  A278799 A278800 A278801 * A278803 A278804 A278805

KEYWORD

nonn

AUTHOR

R. H. Hardin, Nov 28 2016

STATUS

approved

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Last modified January 23 14:42 EST 2022. Contains 350513 sequences. (Running on oeis4.)