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Search: id:A075819
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| A075819 |
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Even squarefree numbers with exactly 3 prime factors. |
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+0
5
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| 30, 42, 66, 70, 78, 102, 110, 114, 130, 138, 154, 170, 174, 182, 186, 190, 222, 230, 238, 246, 258, 266, 282, 286, 290, 310, 318, 322, 354, 366, 370, 374, 402, 406, 410, 418, 426, 430, 434, 438, 442, 470, 474, 494, 498, 506, 518, 530, 534, 574, 582, 590
(list; graph; listen)
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OFFSET
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1,1
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COMMENT
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This sequence first differs from A053858 at 2310=2*3*5*7*11, which is in A053858 but not in this sequence.
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EXAMPLE
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30=2*3*5 and 42=2*3*7 are even, squarefree and have 3 prime factors.
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MAPLE
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ts_3_sod := proc(n); if (numtheory[bigomega](n)=3 and numtheory[mobius](n)=-1 and type(n, even)='true') then RETURN(n); fi end: a3sod := [seq(ts_3_sod(i), i=1..2500)]: a3sod;
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CROSSREFS
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Cf. A053858.
Sequence in context: A007304 A160350 A053858 this_sequence A034683 A087248 A046401
Adjacent sequences: A075816 A075817 A075818 this_sequence A075820 A075821 A075822
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KEYWORD
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easy,nonn
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AUTHOR
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Jani Melik (jani_melik(AT)hotmail.com), Oct 13 2002
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EXTENSIONS
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Edited by Dean Hickerson (dean.hickerson(AT)yahoo.com), Oct 21 2002
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