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A252873
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Number of n X 5 nonnegative integer arrays with upper left 0 and lower right n+5-4 and value increasing by 0 or 1 with every step right or down.
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2
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6, 61, 413, 1953, 7313, 23203, 64920, 164399, 383735, 836797, 1722394, 3373453, 6327844, 11427851, 19956855, 33823579, 55806260, 89871373, 141584051, 218630137, 331472883, 494170691, 725385986, 1049619335, 1498707293
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OFFSET
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1,1
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COMMENTS
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LINKS
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FORMULA
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Empirical: a(n) = (1/259200)*n^10 + (1/6480)*n^9 + (149/60480)*n^8 + (163/7560)*n^7 + (10411/86400)*n^6 + (1027/2160)*n^5 + (16357/12960)*n^4 + (937/810)*n^3 + (1756/1575)*n^2 - (727/630)*n + 3.
Empirical: G.f.: -x*(6 -5*x +72*x^2 -225*x^3 +460*x^4 -612*x^5 +537*x^6 -315*x^7 +121*x^8 -28*x^9 +3*x^10) / (x-1)^11. - R. J. Mathar, Nov 21 2015
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EXAMPLE
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Some solutions for n=3:
..0..1..2..3..4....0..0..0..1..2....0..1..1..1..2....0..0..1..1..2
..1..2..2..3..4....0..0..1..2..3....0..1..2..2..3....1..1..1..2..3
..2..3..3..4..4....0..1..2..3..4....1..2..3..3..4....1..1..2..3..4
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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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