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6, 255255, 33426748355, 1357656019974967471687377449, 7105630242567996762185122555313528897845637444413640621, 1924344668948998025181489521338230544342953524990122861050411878226909135705454891961917517
(list; graph; refs; listen; history; internal format)
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OFFSET
| 1,1
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COMMENTS
| These numbers are [perhaps the smallest] squarefree solutions to the Puzzle 329 of Rivera; a(n) is abundant, not divisible by the first n-1 prime numbers, i.e. the least prime divisor of a(n) is the n-th prime number.
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LINKS
| C. Rivera, Puzzle 329. Odd abundant numbers not divided by 2 or 3.
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FORMULA
| a(n)=A000210[A007684(n)]/A000210(n-1)
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EXAMPLE
| The corresponding sigma[a(n)]/a(n) abundance-ratios are as follows: 2, 2.27462, 2.00097, 2.01433, 2.00101,...;
the terms have 2,3,5,7,11,... as least prime divisors.
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CROSSREFS
| Cf. A000210, A064001, A112640, A007684, A110585, A007684.
Sequence in context: A076909 A172864 A183765 * A067503 A079288 A072234
Adjacent sequences: A112639 A112640 A112641 * A112643 A112644 A112645
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KEYWORD
| nonn
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AUTHOR
| Labos E. (labos(AT)ana.sote.hu), Sep 19 2005
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