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A115973
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Number of distinct prime factors of p^p + 1 where p is prime(n).
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2
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1, 2, 3, 3, 6, 5, 3, 5, 8, 7, 7, 7, 6, 8, 10, 8, 9, 8, 7, 8, 4, 7, 12, 6, 8, 7, 12, 11, 6, 9, 7, 17, 9, 9
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OFFSET
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1,2
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COMMENTS
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LINKS
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EXAMPLE
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If p=29 then (29^29 + 1) contains 7 distinct prime factors.
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MATHEMATICA
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f[n_] := Length@ FactorInteger[Prime[n]^Prime[n] + 1]; Array[f, 20] (* Robert G. Wilson v, Apr 06 2006 *)
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PROG
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(PARI) { for(n=1, 20, p = prime(n); d = factor(p^p+1); dec=matsize(d); print1(dec[1], ", "); ); } \\ R. J. Mathar, Mar 29 2006
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CROSSREFS
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KEYWORD
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nonn,more,hard
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AUTHOR
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EXTENSIONS
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STATUS
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approved
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