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A161841
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Number of factors, with repetition, in all distinct pairs (a=<b) such that a*b = n.
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5
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2, 2, 2, 4, 2, 4, 2, 4, 4, 4, 2, 6, 2, 4, 4, 6, 2, 6, 2, 6, 4, 4, 2, 8, 4, 4, 4, 6, 2, 8, 2, 6, 4, 4, 4, 10, 2, 4, 4, 8, 2, 8, 2, 6, 6, 4, 2, 10, 4, 6, 4, 6, 2, 8, 4, 8, 4, 4, 2, 12, 2, 4, 6, 8, 4, 8, 2, 6, 4, 8, 2, 12, 2, 4, 6, 6, 4, 8, 2, 10, 6, 4, 2, 12, 4, 4, 4, 8, 2, 12, 4, 6, 4, 4, 4, 12, 2, 6, 6, 10
(list; graph; refs; listen; history; internal format)
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OFFSET
| 1,1
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FORMULA
| a(n) = A000005(n)+A010052(n) = A038548(n)*2.
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EXAMPLE
| For n = 16 the a(16)=6 because there are three distict pairs (a=<b) such that a*b = n: The pairs (1,16), (2,8) and (4,4). So the number of factors, with repetition, in all the pairs is equal to 6.
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CROSSREFS
| Cf. A000005, A010052, A038548, A161842.
Sequence in context: A079405 A201353 A072048 * A152674 A072056 A066012
Adjacent sequences: A161838 A161839 A161840 * A161842 A161843 A161844
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KEYWORD
| easy,nonn
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AUTHOR
| Omar E. Pol (info(AT)polprimos.com), Jun 23 2009
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