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A224357 Number of 6Xn 0..2 arrays with diagonals and antidiagonals unimodal and rows nondecreasing 1
729, 46656, 349280, 1351748, 4231138, 12340932, 34697869, 94262290, 246254814, 616242552, 1475123504, 3379586703, 7423803582, 15672970622, 31884279651, 62668814332, 119312143790, 220555944774, 396752366132, 695942226325 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,1

COMMENTS

Row 6 of A224353

LINKS

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

FORMULA

Empirical: a(n) = (761/8553600)*n^12 + (1733/3326400)*n^11 + (1459/108864)*n^10 + (4187/40320)*n^9 + (1551227/1814400)*n^8 + (72841/12600)*n^7 + (1802801/19440)*n^6 - (66259339/120960)*n^5 + (9020552353/1360800)*n^4 - (817656577/50400)*n^3 + (5508355001/83160)*n^2 - (57456263/1540)*n - 269256 for n>7

EXAMPLE

Some solutions for n=3

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

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

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

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

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

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

CROSSREFS

Sequence in context: A036536 A223281 A268976 * A016770 A224016 A059978

Adjacent sequences: A224354 A224355 A224356 * A224358 A224359 A224360

KEYWORD

nonn

AUTHOR

R. H. Hardin Apr 04 2013

STATUS

approved

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Last modified December 6 19:33 EST 2022. Contains 358648 sequences. (Running on oeis4.)