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A266431 Number of 5Xn binary arrays with rows and columns lexicographically nondecreasing and column sums nondecreasing. 1
6, 34, 212, 1391, 8764, 49894, 251381, 1122721, 4490732, 16284683, 54165714, 166968275, 481237398, 1306708520, 3364174219, 8257222586, 19412425379, 43890267973, 95767324137, 202278568268, 414691101885, 827108931171 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,1

COMMENTS

Row 5 of A266428.

LINKS

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

FORMULA

Empirical: a(n) = (1/7602818775552000)*n^19 + (1/47076277248000)*n^18 + (389/266765571072000)*n^17 + (47/815173632000)*n^16 + (11629/7846046208000)*n^15 + (413249/15692092416000)*n^14 + (7941701/23538138624000)*n^13 + (23266079/7242504192000)*n^12 + (14091433/603542016000)*n^11 + (267047/1959552000)*n^10 + (794703337/1207084032000)*n^9 + (14650018639/4828336128000)*n^8 + (267287875667/23538138624000)*n^7 + (102484112767/2139830784000)*n^6 + (39001810891/326918592000)*n^5 + (73310538271/186810624000)*n^4 + (87546462023/102918816000)*n^3 + (113077535/72648576)*n^2 + (469781209/232792560)*n + 1

EXAMPLE

Some solutions for n=4

..0..0..1..1....0..1..1..1....0..0..1..1....0..0..0..1....0..0..0..1

..0..0..1..1....0..1..1..1....0..1..0..1....0..0..1..1....0..0..1..0

..0..0..1..1....0..1..1..1....1..0..1..0....0..1..1..1....0..0..1..1

..0..1..0..0....1..1..1..1....1..1..0..0....1..0..1..1....0..1..1..1

..1..1..0..0....1..1..1..1....1..1..1..1....1..1..1..0....1..1..0..1

CROSSREFS

Cf. A266428.

Sequence in context: A231058 A317178 A218893 * A063090 A184185 A216317

Adjacent sequences:  A266428 A266429 A266430 * A266432 A266433 A266434

KEYWORD

nonn

AUTHOR

R. H. Hardin, Dec 29 2015

STATUS

approved

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Last modified September 19 08:59 EDT 2020. Contains 337178 sequences. (Running on oeis4.)