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A136176
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Number of exponents in the prime-factorization of n which divide n.
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2
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0, 1, 1, 1, 1, 2, 1, 0, 0, 2, 1, 2, 1, 2, 2, 1, 1, 2, 1, 2, 2, 2, 1, 2, 0, 2, 1, 2, 1, 3, 1, 0, 2, 2, 2, 2, 1, 2, 2, 1, 1, 3, 1, 2, 1, 2, 1, 2, 0, 2, 2, 2, 1, 2, 2, 1, 2, 2, 1, 3, 1, 2, 1, 0, 2, 3, 1, 2, 2, 3, 1, 2, 1, 2, 1, 2, 2, 3, 1, 2, 0, 2, 1, 3, 2, 2, 2, 1, 1, 3, 2, 2, 2, 2, 2, 1, 1, 2, 1, 2, 1, 3, 1, 1, 3
(list; graph; refs; listen; history; internal format)
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OFFSET
| 1,6
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EXAMPLE
| 128000 = 2^10 * 5^3. 10 divides 128000, but 3 does not. So a(128000) = 1.
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MATHEMATICA
| Table[Length[Select[Table[FactorInteger[n][[i, 2]], {i, 1, Length[FactorInteger[n]]}], Mod[n, # ] == 0 &]], {n, 1, 90}] - Stefan Steinerberger (stefan.steinerberger(AT)gmail.com), Dec 21 2007
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PROG
| (PARI) A136176(n)=sum(j=1, #t=factor(n)[, 2]~, !(n%t[j])) \\ - M. F. Hasler, Dec 21 2007
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CROSSREFS
| Cf. A136177.
Sequence in context: A161528 A175083 A180026 * A103344 A123484 A008626
Adjacent sequences: A136173 A136174 A136175 * A136177 A136178 A136179
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KEYWORD
| nonn,easy
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AUTHOR
| Leroy Quet, Dec 19 2007
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EXTENSIONS
| More terms from M. F. Hasler (Maximilian.Hasler(AT)gmail.com) and Stefan Steinerberger (stefan.steinerberger(AT)gmail.com), Dec 21 2007
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