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A067024
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Smallest prime p such that p+2 has n distinct prime-factors.
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7
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2, 13, 103, 1153, 15013, 255253, 4849843, 111546433, 4360010653, 100280245063, 5245694198743, 152125131763603, 7149881192889433, 421842990380476663, 16294579238595022363
(list; graph; refs; listen; history; internal format)
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OFFSET
| 1,1
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FORMULA
| a(n) = Min{p; A001221[p+2]=n}
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EXAMPLE
| For n = 1,...,7 the factors of 2+a(n) are as follows: 2.2, 3.5, 3.5.7, 3.5.7.11, 3.5.7.11.13, 3.5.7.11.13.17, 3.5.7.11.13.17.19; i.e. a[n] = A002110(n+1)/2 which is prime for n = 2,..,7.
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CROSSREFS
| Cf. A001221, A002110, A067023, A053705.
Sequence in context: A125589 A007809 A103513 * A083062 A204261 A127746
Adjacent sequences: A067021 A067022 A067023 * A067025 A067026 A067027
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KEYWORD
| nonn
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AUTHOR
| Labos E. (labos(AT)ana.sote.hu), Dec 29 2001
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EXTENSIONS
| a(8)-a(15) from Donovan Johnson (donovan.johnson(AT)yahoo.com), Jan 21 2009
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