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A103178
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Number of divisors of the decimal concatenation of the first n primes.
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0
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2, 2, 4, 2, 8, 8, 4, 8, 8, 8, 32, 24, 8, 16, 8, 16, 16, 16, 4, 8, 8, 16, 8, 24, 16, 64, 4, 32, 8, 128, 32, 32, 128, 128, 192, 16, 16, 64, 16, 768, 8, 48, 256, 128
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OFFSET
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1,1
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LINKS
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FORMULA
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EXAMPLE
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The number of divisors of 2 is 2, so the first term is 2.
The number of divisors of 23 is 2, so the second term is 2.
The number of divisors of 235 is 4, so the third term is 4.
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MATHEMATICA
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Table[DivisorSigma[0, FromDigits[Flatten[Table[IntegerDigits[Prime[j]], {j, 1, n}], 1]]], {n, 1, 100}] (* Labos Elemer, Mar 18 2005 *)
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CROSSREFS
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KEYWORD
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nonn,base,changed
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AUTHOR
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EXTENSIONS
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STATUS
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approved
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