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A252833 Number of n X 5 nonnegative integer arrays with upper left 0 and every value within 2 of its king move distance from the upper left and every value increasing by 0 or 1 with every step right, diagonally se or down. 1
11, 53, 288, 1474, 6068, 18528, 42738, 79563, 129173, 191583, 266793, 354803, 455613, 569223, 695633, 834843, 986853, 1151663, 1329273, 1519683, 1722893, 1938903, 2167713, 2409323, 2663733, 2930943, 3210953, 3503763, 3809373, 4127783 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,1

LINKS

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

FORMULA

Empirical: a(n) = 6400*n^2 - 59190*n + 143483 for n>7.

Conjectures from Colin Barker, Dec 06 2018: (Start)

G.f.: x*(11 + 20*x + 162*x^2 + 758*x^3 + 2457*x^4 + 4458*x^5 + 3884*x^6 + 865*x^7+ 170*x^8 + 15*x^9) / (1 - x)^3.

a(n) = 3*a(n-1) - 3*a(n-2) + a(n-3) for n>10.

(End)

EXAMPLE

Some solutions for n=4:

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

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

..1..1..2..2..3....2..2..2..2..3....1..2..2..2..3....1..1..2..2..3

..1..2..2..2..3....2..3..3..3..3....1..2..2..3..3....2..2..2..3..3

CROSSREFS

Column 5 of A252836.

Sequence in context: A139967 A227965 A196468 * A227255 A104291 A172495

Adjacent sequences:  A252830 A252831 A252832 * A252834 A252835 A252836

KEYWORD

nonn

AUTHOR

R. H. Hardin, Dec 22 2014

STATUS

approved

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Last modified October 26 18:30 EDT 2021. Contains 348268 sequences. (Running on oeis4.)