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A050439
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Fifth-order composites.
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7
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39, 49, 55, 56, 60, 69, 74, 77, 78, 84, 93, 94, 95, 100, 105, 106, 110, 115, 119, 124, 125, 126, 130, 133, 140, 141, 145, 152, 155, 156, 159, 162, 164, 165, 170, 174, 180, 183, 184, 188, 189, 198, 201, 202, 203, 206, 207, 209, 212, 213, 218, 222, 225, 231
(list; graph; refs; listen; history; internal format)
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OFFSET
| 1,1
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LINKS
| N. Fernandez, An order of primeness, F(p)
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FORMULA
| Let C(n) be the n-th composite number, with C(1)=4. Then these are numbers C(C(C(C(C(n))))).
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EXAMPLE
| C(C(C(C(C(8))))) = C(C(C(C(15)))) = C(C(C(25))) = C(C(38)) = C(55) = 77. So 77 is in the sequence.
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MAPLE
| C := remove(isprime, [$4..1000]): seq(C[C[C[C[C[n]]]]], n=1..100);
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CROSSREFS
| A049076-A049081, A006450, A050435, A050436, A050438, A050440.
Sequence in context: A046512 A143746 A064399 * A199993 A181488 A020305
Adjacent sequences: A050436 A050437 A050438 * A050440 A050441 A050442
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KEYWORD
| easy,nonn
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AUTHOR
| Michael Lugo (mlugo(AT)thelabelguy.com), Dec 22 1999
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EXTENSIONS
| More terms from Asher Auel (asher.auel(AT)reed.edu) Dec 15 2000
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