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A255730
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Numbers n such that n^n - (n-1)^n + n is prime.
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0
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OFFSET
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1,2
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COMMENTS
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a(6) corresponds to a prime having 153 digits.
If it exists, a(7) > 5000.
n does not have the form 20k+2 (which leads to a multiple of 5) or 42k+26 (which leads to a multiple of 7).
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LINKS
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EXAMPLE
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4 is in the sequence because 4^4 - 3^4 + 4 = 179 is prime.
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MATHEMATICA
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Select[Range[1000], PrimeQ[#^# - (# - 1)^# + #] &]
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PROG
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(Magma) [n: n in [0..500] |IsPrime(n^n - (n-1)^n + n)];
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CROSSREFS
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KEYWORD
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nonn,more
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AUTHOR
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STATUS
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approved
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