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A223921 Number of 4Xn 0..2 arrays with rows and antidiagonals unimodal and columns nondecreasing 1
15, 225, 2111, 14123, 74040, 323394, 1226491, 4157102, 12856218, 36834899, 98904313, 251078009, 606789828, 1403779390, 3122765753, 6704628063, 13936852281, 28123662137, 55220811463, 105715542647, 197678421680 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,1

COMMENTS

Row 4 of A223918

LINKS

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

FORMULA

Empirical: a(n) = (1/106748928000)*n^16 + (1/2668723200)*n^15 + (29/2335132800)*n^14 + (10013/37362124800)*n^13 + (133979/28740096000)*n^12 + (37333/574801920)*n^11 + (49631/65318400)*n^10 + (1761593/261273600)*n^9 + (219704797/5225472000)*n^8 + (49791911/261273600)*n^7 + (925916249/1437004800)*n^6 + (287406331/179625600)*n^5 + (44691980741/15567552000)*n^4 + (315864449/86486400)*n^3 + (14884357/4324320)*n^2 + (558703/360360)*n + 1

EXAMPLE

Some solutions for n=3

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

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

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

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

CROSSREFS

Sequence in context: A221966 A208080 A224264 * A224191 A224349 A224008

Adjacent sequences:  A223918 A223919 A223920 * A223922 A223923 A223924

KEYWORD

nonn

AUTHOR

R. H. Hardin Mar 29 2013

STATUS

approved

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Last modified May 24 07:35 EDT 2022. Contains 354005 sequences. (Running on oeis4.)