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Search: id:A066472
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| A066472 |
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Numbers having just six anti-divisors. |
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+0 1
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| 32, 49, 50, 60, 72, 81, 121, 128, 145, 180, 181, 196, 264, 288, 324, 361, 480, 529, 684, 685, 961, 1156, 1405, 2304, 2401, 2500, 2521, 2704, 2809, 4624, 4705, 5041, 5184, 7396, 8064, 8581, 9385, 10816, 11881, 13456, 14281, 25600, 26569, 27556, 34585
(list; graph; listen)
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OFFSET
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1,1
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COMMENT
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See A066272 for definition of anti-divisor.
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LINKS
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Jon Perry, The Anti-Divisor
Jon Perry, The Anti-divisor [Cached copy]
Jon Perry, The Anti-divisor: Even More Anti-Divisors [Cached copy]
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MATHEMATICA
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antid[n_] := Select[ Union[ Join[ Select[ Divisors[2n - 1], OddQ[ # ] && # != 1 & ], Select[ Divisors[2n + 1], OddQ[ # ] && # != 1 & ], 2n/Select[ Divisors[ 2*n], OddQ[ # ] && # != 1 &]]] }, # < n & ]]; Select[ Range[10^4], Length[ antid[ # ]] == 6 & ]
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CROSSREFS
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Cf. A066272.
Sequence in context: A043202 A043982 A045023 this_sequence A037008 A099048 A048734
Adjacent sequences: A066469 A066470 A066471 this_sequence A066473 A066474 A066475
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KEYWORD
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nonn
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AUTHOR
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Robert G. Wilson v (rgwv(AT)rgwv.com), Jan 02 2002
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