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A252975 Number of nX7 nonnegative integer arrays with upper left 0 and lower right n+7-5 and value increasing by 0 or 1 with every step right or down 2
20, 483, 8694, 112877, 1100210, 8528422, 54926890, 303382053, 1471499970, 6383377435, 25130419118, 90859574359, 304675148476, 955390407363, 2821209579406, 7892066379909, 21022079637900, 53557533613173 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,1

COMMENTS

Column 7 of A252976

LINKS

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

FORMULA

Empirical: a(n) = (491/510909421717094400)*n^21 + (491/4054836680294400)*n^20 + (31237/4561691265331200)*n^19 + (16931/72754246656000)*n^18 + (6860417/1280474741145600)*n^17 + (5620079/62768369664000)*n^16 + (28238557/24715045555200)*n^15 + (460147/39626496000)*n^14 + (1994012479/20542375526400)*n^13 + (9803403773/14485008384000)*n^12 + (2842330237/724250419200)*n^11 + (22704330871/1207084032000)*n^10 + (117780405261823/1581762915532800)*n^9 + (1372309011587/5706215424000)*n^8 + (17399771450683/28245766348800)*n^7 + (29498769372031/23538138624000)*n^6 + (57797311549729/26676557107200)*n^5 + (6071375333369/2020951296000)*n^4 + (7008309815167/1119943843200)*n^3 + (375662307017/83805321600)*n^2 + (152121493/25865840)*n - 4

EXAMPLE

Some solutions for n=4

..0..1..2..3..3..3..4....0..1..1..2..2..3..4....0..0..1..2..3..3..3

..1..2..2..3..3..3..4....1..1..2..3..3..4..5....1..1..1..2..3..4..4

..2..2..2..3..3..4..5....2..2..3..3..4..5..6....1..1..2..2..3..4..5

..2..3..3..4..4..5..6....2..3..4..4..5..6..6....1..1..2..3..4..5..6

CROSSREFS

Sequence in context: A324069 A065412 A159753 * A000827 A241261 A118552

Adjacent sequences:  A252972 A252973 A252974 * A252976 A252977 A252978

KEYWORD

nonn

AUTHOR

R. H. Hardin, Dec 25 2014

STATUS

approved

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Last modified August 12 00:34 EDT 2022. Contains 356067 sequences. (Running on oeis4.)