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A337689
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Numbers divisible by 3 or more primitive nondeficient numbers.
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4
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140, 280, 420, 560, 700, 840, 980, 1120, 1144, 1260, 1320, 1400, 1540, 1560, 1680, 1820, 1848, 1890, 1960, 2100, 2184, 2200, 2240, 2288, 2380, 2520, 2600, 2640, 2660, 2800, 2860, 2940, 2992, 3080, 3120, 3150, 3220, 3300, 3344, 3360, 3432, 3500, 3640, 3696, 3740
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OFFSET
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1,1
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COMMENTS
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A006039 lists the primitive nondeficient numbers.
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LINKS
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FORMULA
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Numbers k such that A337690(k) >= 3.
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EXAMPLE
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Table of n, a(n) and the relevant divisors starts:
1 140 20, 28, 70;
2 280 20, 28, 70;
3 420 6, 20, 28, 70;
4 560 20, 28, 70;
5 700 20, 28, 70;
6 840 6, 20, 28, 70;
7 980 20, 28, 70;
8 1120 20, 28, 70;
9 1144 88, 104, 572;
10 1260 6, 20, 28, 70;
11 1320 6, 20, 88;
12 1400 20, 28, 70;
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PROG
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CROSSREFS
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KEYWORD
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nonn,easy
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AUTHOR
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STATUS
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approved
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