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A122824
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Prime(semiprime(n)) - semiprime(prime(n)). Commutator [A000040,A001358] at n.
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11
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1, 4, 9, 8, 10, 12, 24, 24, 32, 15, 46, 24, 27, 34, 25, 40, 44, 46, 51, 54, 53, 46, 54, 60, 70, 70, 98, 105, 104, 91, 64, 72, 38, 33, 80, 105, 112, 110, 108, 88, 82, 66, 72, 84, 76, 124, 103, 60, 51, 58, 114, 116, 120, 68
(list; graph; refs; listen; history; internal format)
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OFFSET
| 1,2
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FORMULA
| a(n) = A106349(n) - A106350(n).
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EXAMPLE
| a(1) = prime(semiprime(1)) - semiprime(prime(1)) = prime(4) - semiprime(2) = 7 - 6 = 1.
a(2) = prime(semiprime(2)) - semiprime(prime(2)) = prime(6) - semiprime(3) = 13 - 9 = 4.
a(3) = prime(semiprime(3)) - semiprime(prime(3)) = prime(9) - semiprime(5) = 23 - 14 = 9.
a(4) = prime(semiprime(4)) - semiprime(prime(4)) = prime(10) - semiprime(7) = 29 - 21 = 8.
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CROSSREFS
| Cf. A000040, A001358, A106349, A106350.
Sequence in context: A188658 A019784 A011381 * A179396 A093491 A140808
Adjacent sequences: A122821 A122822 A122823 * A122825 A122826 A122827
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KEYWORD
| easy,nonn
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AUTHOR
| Jonathan Vos Post (jvospost3(AT)gmail.com), Oct 23 2006
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