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A054462
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Numbers n such that (n+1)^n + n^(n-1) is prime.
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0
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OFFSET
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1,2
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LINKS
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MATHEMATICA
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Select[Range[1000], PrimeQ[(# + 1)^# + #^(# - 1)] &] (* Vincenzo Librandi Sep 27 2012 *)
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PROG
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(PARI) xp1toxp1(n)= { sr=0; forstep(x=2, n, 1, y=(x+1)^x + x^(x-1); if(ispseudoprime(y), print(x" "y" "); sr+= 1.0/y; ) ); print(); print(sr) }
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CROSSREFS
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KEYWORD
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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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