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Search: id:A046312
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| A046312 |
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Numbers that are divisible by exactly 9 primes (counted with multiplicity). |
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17
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| 512, 768, 1152, 1280, 1728, 1792, 1920, 2592, 2688, 2816, 2880, 3200, 3328, 3888, 4032, 4224, 4320, 4352, 4480, 4800, 4864, 4992, 5832, 5888, 6048, 6272, 6336, 6480, 6528, 6720, 7040, 7200, 7296, 7424, 7488, 7936, 8000, 8320, 8748, 8832, 9072, 9408
(list; graph; listen)
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OFFSET
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1,1
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COMMENT
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Also called 9-almost primes. Products of exactly 9 primes (not necessarily distinct). - Jonathan Vos Post (jvospost2(AT)yahoo.com), Dec 11 2004
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LINKS
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T. D. Noe, Table of n, a(n) for n=1..10000
Eric Weisstein's World of Mathematics, Reference
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FORMULA
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Product p_i^e_i with Sum e_i = 9.
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MATHEMATICA
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Select[Range[2200], Plus @@ Last /@ FactorInteger[ # ] == 9 &] - Vladimir Orlovsky, Apr 23 2008
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CROSSREFS
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Cf. A046311, A120050 (number of 9-almost primes <= 10^n).
Cf. A014612, A014613, A001358, A101637, A101638, A101605, A101606.
Adjacent sequences: A046309 A046310 A046311 this_sequence A046313 A046314 A046315
Sequence in context: A045003 A046311 A036333 this_sequence A045033 A066648 A043423
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KEYWORD
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nonn
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AUTHOR
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Patrick De Geest (pdg(AT)worldofnumbers.com), Jun 15 1998.
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