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Search: id:A124309
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| A124309 |
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5-almost primes indexed by primes. |
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+0
5
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| 48, 72, 108, 120, 180, 208, 270, 280, 368, 420, 450, 520, 592, 612, 660
(list; graph; listen)
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OFFSET
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1,1
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FORMULA
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a(n) = 5almostprime(prime(n)) = A014614(A000040(n)).
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EXAMPLE
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a(1) = 5almostprime(prime(1)) = 5almostprime(2) = 48 = 2^4 * 3.
a(2) = 5almostprime(prime(2)) = 5almostprime(3) = 72 = 2^3 * 3^2.
a(3) = 5almostprime(prime(3)) = 5almostprime(5) = 108 = 2^2 * 3^3.
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CROSSREFS
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Cf. A124308 Primes indexed by 5-almost primes. A124310 prime(5almostprime(n)) - 5almostprime(prime(n)). 4-almost primes indexed by primes = A124283. prime(4almostprime(n)) - 4almostprime(prime(n)) = A124284. Primes indexed by 3-almost primes = A124268. 3-almost primes indexed by primes = A124269. prime(3almostprime(n)) - 3almostprime(prime(n)) = A124270. See also A106349 Primes indexed by semiprimes. See also A106350 Semiprimes indexed by primes. See also A122824 Prime(semiprime(n)) - semiprime(prime(n)). Commutator [A000040, A001358] at n.
Cf. A000040, A014614, A114405, A114415, A122824, A124269, A124270, A124282-A124284, A124309, A124310.
Sequence in context: A043157 A039334 A043937 this_sequence A112058 A033821 A165039
Adjacent sequences: A124306 A124307 A124308 this_sequence A124310 A124311 A124312
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KEYWORD
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easy,nonn,less
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AUTHOR
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Jonathan Vos Post (jvospost3(AT)gmail.com), Oct 25 2006
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