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A338778
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Number of ordered ways of writing n-th tetrahedral number as a sum of n positive tetrahedral numbers.
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1
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1, 1, 0, 0, 0, 20, 195, 1890, 6286, 94584, 1065120, 12345432, 194450586, 2844976135, 44569913570, 740023110855, 13144353701940, 241663182769494, 4707408836458200, 95865898167054186, 2038122531703155798, 45103282424247100962, 1037559653596650520776, 24776005985596646165127
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OFFSET
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0,6
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LINKS
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FORMULA
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EXAMPLE
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The 5th tetrahedral number is 35 and 35 = 1 + 4 + 10 + 10 + 10 (20 permutations), so a(5) = 20.
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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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