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A079476
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First prime greater than or equal to phi(n^2).
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1
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2, 2, 7, 11, 23, 13, 43, 37, 59, 41, 113, 53, 157, 89, 127, 131, 277, 109, 347, 163, 257, 223, 509, 193, 503, 313, 487, 337, 821, 241, 937, 521, 661, 547, 853, 433, 1361, 691, 937, 641, 1657, 509, 1811, 881, 1087, 1013, 2179, 769, 2063, 1009, 1637, 1249, 2767
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OFFSET
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1,1
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COMMENTS
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The sequence generally goes up,down,up,down...
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LINKS
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FORMULA
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EXAMPLE
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phi(3^2)=phi(9)=6, therefore a(3)=7.
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MAPLE
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map(t -> nextprime(numtheory:-phi(t^2)-1), [$1..100]); # Robert Israel, Oct 25 2017
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MATHEMATICA
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Array[If[PrimeQ@ #, #, NextPrime@ #] &@ EulerPhi[#^2] &, 53] (* Michael De Vlieger, Oct 25 2017 *)
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PROG
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(PARI) for (n=1, 100, print1(nextprime(eulerphi(n^2))", "))
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CROSSREFS
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KEYWORD
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AUTHOR
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EXTENSIONS
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STATUS
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approved
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