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A252834 Number of n X 6 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
16, 85, 529, 3365, 18528, 78674, 244131, 569420, 1070036, 1750150, 2610438, 3650950, 4871686, 6272646, 7853830, 9615238, 11556870, 13678726, 15980806, 18463110, 21125638, 23968390, 26991366, 30194566, 33577990, 37141638, 40885510 (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) = 90112*n^2 - 1032064*n + 3059590 for n>9.

Conjectures from Colin Barker, Dec 07 2018: (Start)

G.f.: x*(16 + 37*x + 322*x^2 + 2017*x^3 + 9935*x^4 + 32656*x^5 + 60328*x^6 + 54521*x^7 + 15495*x^8 + 4171*x^9 + 676*x^10 + 50*x^11) / (1 - x)^3.

a(n) = 3*a(n-1) - 3*a(n-2) + a(n-3) for n>12.

(End)

EXAMPLE

Some solutions for n=4:

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

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

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

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

CROSSREFS

Column 6 of A252836.

Sequence in context: A231941 A118675 A223962 * A050256 A223835 A224143

Adjacent sequences:  A252831 A252832 A252833 * A252835 A252836 A252837

KEYWORD

nonn

AUTHOR

R. H. Hardin, Dec 22 2014

STATUS

approved

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Last modified July 15 22:48 EDT 2019. Contains 325061 sequences. (Running on oeis4.)