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A069461
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Number of distinct prime factors of prime(n)^n-1.
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3
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0, 1, 2, 3, 3, 5, 2, 6, 6, 8, 7, 11, 5, 7, 9, 8, 5, 12, 4, 13, 8, 10, 4, 16, 7, 12, 12, 13, 6, 18, 4, 15, 10, 8, 10, 19, 8, 9, 8, 17, 5, 21, 5, 13, 16, 16, 6, 21, 9, 12, 9, 15
(list; graph; refs; listen; history; internal format)
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OFFSET
| 1,3
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COMMENTS
| a(n) = A001221(A069459(n)).
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LINKS
| Dario Alpern, Factorization using the Elliptic Curve Method.
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EXAMPLE
| A000040(8)^8-1=19^8-1=16983563040=2^5*3^2*5*17*181*3833, therefore a(8)=6 and A069462(8)=11.
A000040(9)^9-1=23^9-1=1801152661462=2*7*11*19*79*7792003, therefore a(9)=6 and A069462(9)=6.
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PROG
| (PARI) for(n=1, 52, print1(omega(prime(n)^n-1)", ")) - Herman Jamke (hermanjamke(AT)fastmail.fm), Jan 03 2008
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CROSSREFS
| Cf. A069464, A069462.
Sequence in context: A049272 A181483 A205130 * A063256 A131320 A119912
Adjacent sequences: A069458 A069459 A069460 * A069462 A069463 A069464
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KEYWORD
| nonn
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AUTHOR
| Reinhard Zumkeller (reinhard.zumkeller(AT)gmail.com), Mar 24 2002
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EXTENSIONS
| More terms from Hugo Pfoertner (hugo(AT)pfoertner.org), May 18 2004
More terms from Herman Jamke (hermanjamke(AT)fastmail.fm), Jan 03 2008
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