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A066306
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Prime numbers such that sum of digits equals product of digits.
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9
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2, 3, 5, 7, 2141, 2411, 4211, 11251, 12511, 15121, 21221, 25111, 1112171, 1127111, 1172111, 1271111, 7112111, 11112811, 11128111, 11218111, 12111811, 12118111, 12181111, 18211111, 81111211, 81112111
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OFFSET
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1,1
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LINKS
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EXAMPLE
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2141 = p[323], 2*1*4*1 = 8 = 2+1+4+1.
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MATHEMATICA
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f[n_] := IntegerDigits[ Prime[n]]; Prime[ Select[ Range[ PrimePi[10^10]], Apply[Plus, f[ # ]] == Apply[Times, f[ # ]] & ]]
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PROG
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(Magma) [NthPrime(n): n in [1..2*10^4] | &+Intseq(NthPrime(n)) eq &*Intseq(NthPrime(n))]; // Vincenzo Librandi, Nov 18 2015
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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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