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A068794
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In prime factorization of n replace all primes with the least prime factor of n; a(1)=1.
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7
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1, 2, 3, 4, 5, 4, 7, 8, 9, 4, 11, 8, 13, 4, 9, 16, 17, 8, 19, 8, 9, 4, 23, 16, 25, 4, 27, 8, 29, 8, 31, 32, 9, 4, 25, 16, 37, 4, 9, 16, 41, 8, 43, 8, 27, 4, 47, 32, 49, 8, 9, 8, 53, 16, 25, 16, 9, 4, 59, 16, 61, 4, 27, 64, 25, 8, 67, 8, 9, 8, 71, 32
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OFFSET
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1,2
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COMMENTS
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a(n) = A068795(n) iff n=1 or n=p^k for some prime p, k>0.
a(30)=a(2*3*5)=2*2*2=8.
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LINKS
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FORMULA
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MATHEMATICA
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lpf[n_]:=Module[{fi=FactorInteger[n]}, Times@@PadRight[{}, Total[ fi[[All, 2]]], fi[[1, 1]]]]; Array[lpf, 80] (* Harvey P. Dale, Apr 14 2020 *)
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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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