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A120335
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CRF(13): consecutive refactorable numbers (rf, rf-1 are refactorable) such that 13 is the smallest prime divisor of rf.
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OFFSET
| 1,1
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COMMENTS
| The sequence has prime factorization (13*197)^12, (13*1093)^12, (13*1733)^12, (13*17*139)^12, (13*7877)^12, (13*16069)^12.
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FORMULA
| a(n) = is the n-th number rf such that both rf and rf-1 are refactorable and 13 is the smallest prime divisor of rf.
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EXAMPLE
| a(1)=(13*197)^12 is the first number rf such that rf refactorable, 13 is the smallest prime of rf and rf-1 is refactorable.
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CROSSREFS
| Cf. A033950, A036898, A114617.
Sequence in context: A095474 A003944 A003937 * A095476 A181789 A095478
Adjacent sequences: A120332 A120333 A120334 * A120336 A120337 A120338
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KEYWORD
| nonn,bref
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AUTHOR
| Walter Kehowski (wkehowski(AT)cox.net), Jun 22 2006
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