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A252833
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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.
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1
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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
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OFFSET
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1,1
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LINKS
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FORMULA
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Empirical: a(n) = 6400*n^2 - 59190*n + 143483 for n>7.
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)
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EXAMPLE
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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
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CROSSREFS
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KEYWORD
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nonn
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AUTHOR
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STATUS
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approved
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