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A048863
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Number of nonprimes (1 and composites) in the reduced residue system of n-th primorial number (A002110).
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2
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1, 1, 1, 6, 142, 2518, 49836, 1012859, 24211838, 721500294, 22627459401, 844130935668, 34729870646918
(list; graph; refs; listen; history; internal format)
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OFFSET
| 1,4
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FORMULA
| A005867(n) - [ A000849(n) - A001221(A002110(n)) ] = A000010(A002110(n)) - [ A000720((A002110(n)) - n ]
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EXAMPLE
| n=3, 3rd primorial is 30, EulerPhi(30)=8, a(3)=1 since 1 is regarded here a nonprime. See A048597. n=4, 4th primorial is 210, size of its reduced residue system(RRS) is 48 of 6 is either composite or 1: {1,121,143,169,187,209}.
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CROSSREFS
| Cf. A002110, A000010, A005867, A000720, A048597, A007625, A048862.
A048683(n) = A005867(n) -A000849(n) + n.
Sequence in context: A193502 A059488 A067196 * A111839 A196811 A200457
Adjacent sequences: A048860 A048861 A048862 * A048864 A048865 A048866
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KEYWORD
| more,nonn
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AUTHOR
| Labos E. (labos(AT)ana.sote.hu)
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