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A162730
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Semiprimes of the form n=pq where q=kp-k+1, p,q primes and k > 1
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0
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6, 10, 14, 15, 21, 22, 26, 33, 34, 38, 39, 46, 51, 57, 58, 62, 65, 69, 74, 82, 85, 86, 87, 91, 93, 94, 106, 111, 118, 122, 123, 129, 133, 134, 141, 142, 145, 146, 158, 159, 166, 177, 178, 183, 185, 194, 201, 202, 205, 206, 213, 214, 217, 218, 219, 226, 237, 249, 254
(list; graph; refs; listen; history; internal format)
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OFFSET
| 1,1
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COMMENTS
| It seems that most of the semiprimes of this form (but not all, only those satisfying an aditional property) can be factored very quickly (e.g. numbers with up to 1200 decimal digits can be factored in a couple of seconds) using a very simple method
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CROSSREFS
| Sequence in context: A201650 A201514 A201464 * A180074 A093772 A046400
Adjacent sequences: A162727 A162728 A162729 * A162731 A162732 A162733
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KEYWORD
| nonn
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AUTHOR
| Vassilis Papadimitriou (bpapa(AT)sch.gr), Jul 12 2009, Jul 13 2009
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EXTENSIONS
| More terms from R. J. Mathar (mathar(AT)strw.leidenuniv.nl), Aug 06 2009
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