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Search: id:A046306
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| A046306 |
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Numbers that are divisible by exactly 6 primes (counted with multiplicity). |
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+0 33
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| 64, 96, 144, 160, 216, 224, 240, 324, 336, 352, 360, 400, 416, 486, 504, 528, 540, 544, 560, 600, 608, 624, 729, 736, 756, 784, 792, 810, 816, 840, 880, 900, 912, 928, 936, 992, 1000, 1040, 1104, 1134, 1176, 1184, 1188, 1215, 1224, 1232, 1260, 1312, 1320
(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 6-almost primes. Products of exactly 6 primes (not necessarily distinct). Any 6-almost prime can be represented in several ways as a product of two 3-almost primes A014612, and in several ways as a product of three semiprimes A001358. - 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 = 6.
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MATHEMATICA
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Select[Range[500], Plus @@ Last /@ FactorInteger[ # ] == 6 &] - Vladimir Orlovsky, Apr 23 2008
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CROSSREFS
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Cf. A046305, A120047 (number of 6-almost primes <= 10^n).
Cf. A014612, A001358, A101605, A101606.
Sequence in context: A046305 A114828 A036330 this_sequence A104022 A061099 A118488
Adjacent sequences: A046303 A046304 A046305 this_sequence A046307 A046308 A046309
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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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