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A219678
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Number of tripartite partitions of (n,n,n) into triples.
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3
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1, 5, 66, 686, 6721, 58616, 476781, 3608348, 25781989, 174810494, 1132328205, 7037425172, 42140788751, 243918472743, 1368647208107, 7462686474948, 39626100989332, 205283558905562, 1039263967957447, 5149048724566723, 24998922141116056, 119073277412589351
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OFFSET
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0,2
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COMMENTS
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a(n) is also the number of factorizations of m^n where m is a product of 3 distinct primes. a(1) = 5: (2*3*5)^1 = 30 has 5 factorizations: 30, 5*6, 3*10, 2*3*5, 2*15.
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LINKS
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EXAMPLE
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a(1) = 5: [(1,1,1)], [(1,1,0),(0,0,1)], [(1,0,1),(0,1,0)], [(1,0,0),(0,1,0),(0,0,1)], [(0,1,1),(1,0,0)].
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CROSSREFS
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KEYWORD
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nonn
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AUTHOR
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EXTENSIONS
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STATUS
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approved
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