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Search: id:A057809
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| A057809 |
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Numbers n such that pi(n) divides n. |
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+0
25
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| 2, 4, 6, 8, 27, 30, 33, 96, 100, 120, 330, 335, 340, 350, 355, 360, 1008, 1080, 1092, 1116, 1122, 1128, 1134, 3059, 3066, 3073, 3080, 3087, 3094, 8408, 8424, 8440, 8456, 8464, 8472, 23526, 23535, 24300, 64540, 64580, 64610, 64620, 64650, 64690, 64700
(list; graph; listen)
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OFFSET
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1,1
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COMMENT
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Each cluster of entries is approximately a power of e from the previous cluster.
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EXAMPLE
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120 is a member as there are exactly 30 primes less than 120 and 30*4 = 120.
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MATHEMATICA
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Select[ Range[2, 10^5], IntegerQ[ # / PrimePi[ # ]] & ]
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CROSSREFS
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Cf. A000720, A057810, A071394, A038627. Apart from initial term same as A058011.
Sequence in context: A067732 A117912 A092047 this_sequence A135632 A068541 A108425
Adjacent sequences: A057806 A057807 A057808 this_sequence A057810 A057811 A057812
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KEYWORD
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nonn
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AUTHOR
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N. J. A. Sloane (njas(AT)research.att.com), Nov 07 2000
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EXTENSIONS
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More terms from James A. Sellers (sellersj(AT)math.psu.edu), Nov 08 2000
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