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Search: id:A063948
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| A063948 |
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Unitary untouchable numbers: us(x)=n has no solution where us(x) (A063919) is the sum of the proper unitary divisors of x. |
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+0
2
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| 2, 3, 4, 5, 7, 374, 702, 758, 998, 1542, 1598, 1778, 1808, 1830, 1974, 2378, 2430, 2910, 3164, 3182, 3188, 3216, 3506, 3540, 3666, 3698, 3818, 3846, 3986, 4196, 4230, 4574, 4718, 4782, 5126, 5324, 5610, 5738, 5918, 5952, 6002, 6174, 6270, 6404, 6450, 6510
(list; graph; listen)
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OFFSET
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1,1
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FORMULA
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If us(x) = n > 1, then n^2 - 4x >= 0. - Dean Hickerson, Sep 04, 2001.
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CROSSREFS
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Cf. A034448, A063919, A064000.
Adjacent sequences: A063945 A063946 A063947 this_sequence A063949 A063950 A063951
Sequence in context: A096841 A029963 A028986 this_sequence A113929 A082351 A122319
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KEYWORD
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nonn,easy,nice
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AUTHOR
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felice.russo(AT)katamail.com, Sep 04, 2001
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EXTENSIONS
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More terms from David W. Wilson, Sep 05, 2001
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