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A356078
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Highly composite numbers that are multiples of their number of divisors.
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1
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1, 2, 12, 24, 36, 60, 180, 240, 360, 720, 1260, 1680, 5040, 10080, 15120, 20160, 25200, 55440, 110880, 221760, 277200, 665280, 720720, 1441440, 2882880, 3603600, 8648640, 14414400, 32432400, 43243200, 61261200, 245044800, 551350800, 735134400, 1102701600, 2205403200
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OFFSET
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1,2
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COMMENTS
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Conjecture: this sequence is finite. The prime factorization of the number of divisors of a large highly composite number usually has a high power of 2; this is not true of the number of divisors of a highly composite number itself.
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LINKS
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EXAMPLE
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180 (in A002182) has 18 divisors, and 180/18 equals 10; so, 180 is in this sequence.
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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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