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Search: id:A112998
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| A112998 |
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Numbers n such that n, n+1, and n+2 are 1,2,3-semiprimes. |
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+0
2
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| 61, 73, 193, 277, 397, 421, 613, 661, 757, 1093, 1237, 1453, 1657, 2137, 2341, 2593, 2797, 2917, 3217, 4177, 4621, 5233, 6121, 6133, 6217, 7057, 7537
(list; graph; listen)
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OFFSET
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1,1
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LINKS
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Zak Seidov, Table of n, a(n) for n = 1..1000
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EXAMPLE
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61 is prime, 62=2*31 is semiprime, 63=3*3*7 is 3-semiprime.
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MATHEMATICA
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Do[p=Prime[n]; If[Total[FactorInteger[p+1]][[2]]==2&&Total[FactorInteger[p+2]][[2]]==3, Print[p]], {n, 1, 1000}];
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CROSSREFS
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Adjacent sequences: A112995 A112996 A112997 this_sequence A112999 A113000 A113001
Sequence in context: A139944 A033236 A141457 this_sequence A118162 A139931 A103812
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KEYWORD
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nonn
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AUTHOR
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Zak Seidov (zakseidov(AT)yahoo.com), Jan 03 2006
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