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A102246
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Number of distinct prime factors of prime p concatenated p-1 times.
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1
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1, 2, 3, 5, 7, 9, 10, 10, 10, 11, 19, 16, 14, 20, 9, 12
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OFFSET
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1,2
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LINKS
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EXAMPLE
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If p=2, then the number of distinct prime factors of 2 is 1 since 2 is prime.
If p=3, then the number of distinct prime factors of 33 is 2.
If p=5, then the number of distinct prime factors of 5555 is 3.
If p=7, then the number of distinct prime factors of 777777 is 5.
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MATHEMATICA
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f[n_] := Length[ FactorInteger[ FromDigits[ Flatten[ Table[ IntegerDigits[ Prime[n]], {Prime[n] - 1}]] ]]]; Table[ f[n], {n, 10}]
dpf[n_]:=Module[{p=Prime[n]}, PrimeNu[FromDigits[Flatten[ IntegerDigits/@ Table[p, {p-1}]]]]]; Array[dpf, 16] (* Harvey P. Dale, Aug 20 2013 *)
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CROSSREFS
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KEYWORD
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nonn,base
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AUTHOR
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EXTENSIONS
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STATUS
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approved
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