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A252980 Number of n X 5 nonnegative integer arrays with upper left 0 and lower right its king-move distance away minus 2 and every value increasing by 0 or 1 with every step right, diagonally se or down. 2
6, 41, 266, 1247, 4657, 67537, 433401, 1481460, 3510600, 6637020, 10878576, 16235268, 22707096, 30294060, 38996160, 48813396, 59745768, 71793276, 84955920, 99233700, 114626616, 131134668, 148757856, 167496180, 187349640, 208318236 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,1

COMMENTS

Column 5 of A252983.

LINKS

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

FORMULA

Empirical: a(n) = 557568*n^2 - 7467372*n + 25553940 for n>8.

Conjectures from Colin Barker, Mar 20 2018: (Start)

G.f.: x*(6 + 23*x + 161*x^2 + 566*x^3 + 1673*x^4 + 57041*x^5 + 243514*x^6 + 379211*x^7 + 298886*x^8 + 116199*x^9 + 17856*x^10) / (1 - x)^3.

a(n) = 3*a(n-1) - 3*a(n-2) + a(n-3) for n>11.

(End)

EXAMPLE

Some solutions for n=4:

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

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

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

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

CROSSREFS

Cf. A252983.

Sequence in context: A266425 A194781 A323969 * A274997 A015551 A291018

Adjacent sequences:  A252977 A252978 A252979 * A252981 A252982 A252983

KEYWORD

nonn

AUTHOR

R. H. Hardin, Dec 25 2014

STATUS

approved

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Last modified September 29 04:24 EDT 2022. Contains 357082 sequences. (Running on oeis4.)