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A124876
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Number of factors in factorization of A007408(n).
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2
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0, 2, 1, 3, 2, 4, 3, 2, 3, 5, 3, 3, 3, 2, 1, 4, 2, 5, 1, 3, 2, 6, 2, 4, 2, 1, 3, 5, 3, 6, 1, 2, 3, 2, 3, 10, 4, 4, 5, 5, 8, 7, 7, 2, 4, 7, 3, 2, 4
(list; graph; refs; listen; history; internal format)
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OFFSET
| 1,2
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FORMULA
| a(n) = A001222(A007408(n)). - R. J. Mathar (mathar(AT)strw.leidenuniv.nl), May 18 2007
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EXAMPLE
| a(1) = 0 since A007408(1)= 1 contains no prime factor,
a(2) = 2 since A007408(2)= 9 = 3 x 3,
a(3) = 1 since A007408(3)= 251 is prime,
a(6) = 4 since A007408(6)= 7 x 7 x 11 x 53.
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MAPLE
| seq( add(op(2, j), j=op(2, (ifactors@A007408)(n))), n=1..28 );
A001222 := proc(n) numtheory[bigomega](n) ; end: b := fscanf("b007408.txt", "%d %d") : while b <> [] do printf("%d, ", A001222(op(2, b))) ; b := fscanf("b007408.txt", "%d %d") : od : - R. J. Mathar (mathar(AT)strw.leidenuniv.nl), May 18 2007
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CROSSREFS
| Cf. A007408, A124877, A124787.
Sequence in context: A051282 A052306 A046823 * A188901 A171618 A026238
Adjacent sequences: A124873 A124874 A124875 * A124877 A124878 A124879
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KEYWORD
| nonn
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AUTHOR
| M. F. Hasler (Maximilian.Hasler(AT)gmail.com), Nov 11 2006
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EXTENSIONS
| More terms from R. J. Mathar (mathar(AT)strw.leidenuniv.nl), May 18 2007
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