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A252478
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Products of a semiprime times a larger prime.
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2
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20, 28, 42, 44, 52, 66, 68, 76, 78, 92, 99, 102, 110, 114, 116, 117, 124, 130, 138, 148, 153, 164, 170, 171, 172, 174, 186, 188, 190, 207, 212, 222, 230, 236, 238, 244, 246, 255, 258, 261, 266, 268, 279, 282, 284, 285, 290, 292, 310, 316, 318, 322, 332, 333, 345, 354, 356, 366, 369, 370
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OFFSET
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1,1
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COMMENTS
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Primitive elements of the sequence A137428 of numbers which have a composite divisor smaller than their largest prime factor: That sequence consists of all multiples of the terms of this sequence.
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LINKS
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FORMULA
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PROG
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(PARI) is(n)={bittest(12, #f=factor(n)~) && f[1, #f]^2>n && setsearch([[2, 1], [1, 1, 1]], f[2, ])}
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CROSSREFS
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KEYWORD
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nonn
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AUTHOR
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STATUS
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approved
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