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A108777
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Numbers n such that a^t + b^t + c^t + ... is prime, where a*b*c* ... is the prime factorization of n with multiplicity and t is the reversal of n.
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0
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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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a(3)=75 because 75=3*5^2 and 75 reversed is 57 and 3^57 + 5^57 + 5^57 = 13877787807816026798194477932746894440813, a prime.
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MATHEMATICA
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fQ[n_] := PrimeQ[Plus @@ (Flatten[ Table[ #[[1]], {#[[2]]}] & /@ FactorInteger[n]]^FromDigits[ Reverse[ IntegerDigits[ n]] ])]; Do[ If[ fQ[n], Print[n]], {n, 2200}] (* Robert G. Wilson v, Jun 28 2005 *)
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CROSSREFS
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KEYWORD
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base,more,nonn
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AUTHOR
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EXTENSIONS
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STATUS
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approved
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