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A253220 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 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
6, 25, 102, 268, 268, 3568, 16028, 40238, 77063, 126673, 189083, 264293, 352303, 453113, 566723, 693133, 832343, 984353, 1149163, 1326773, 1517183, 1720393, 1936403, 2165213, 2406823, 2661233, 2928443, 3208453, 3501263, 3806873, 4125283 (list; graph; refs; listen; history; text; internal format)
OFFSET
1,1
LINKS
FORMULA
Empirical: a(n) = 6400*n^2 - 71990*n + 206573 for n>8.
Conjectures from Colin Barker, Dec 10 2018: (Start)
G.f.: x*(6 + 7*x + 45*x^2 + 31*x^3 - 255*x^4 + 3466*x^5 + 5860*x^6 + 2590*x^7 + 865*x^8 + 170*x^9 + 15*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..1..1..1..2....0..1..1..2..2....0..0..0..1..2....0..0..0..1..2
..1..1..1..1..2....0..1..1..2..2....0..0..0..1..2....1..1..1..1..2
..1..1..2..2..2....1..1..2..2..2....0..1..1..1..2....1..1..2..2..2
..1..2..2..2..2....2..2..2..2..2....1..1..2..2..2....2..2..2..2..2
CROSSREFS
Column 5 of A253223.
Sequence in context: A346390 A323824 A037537 * A037481 A199844 A267536
KEYWORD
nonn
AUTHOR
R. H. Hardin, Dec 29 2014
STATUS
approved

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Last modified March 29 07:27 EDT 2024. Contains 371265 sequences. (Running on oeis4.)