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A302491
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Prime numbers of squarefree index.
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14
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2, 3, 5, 11, 13, 17, 29, 31, 41, 43, 47, 59, 67, 73, 79, 83, 101, 109, 113, 127, 137, 139, 149, 157, 163, 167, 179, 181, 191, 199, 211, 233, 241, 257, 269, 271, 277, 283, 293, 313, 317, 331, 347, 349, 353, 367, 373, 389, 397, 401, 421, 431, 439, 443, 449, 461
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OFFSET
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1,1
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COMMENTS
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A prime index of n is a number m such that prime(m) divides n.
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LINKS
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FORMULA
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MAPLE
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map(ithprime, select(numtheory:-issqrfree, [$1..500])); # Robert Israel, Nov 06 2023
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MATHEMATICA
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Prime/@Select[Range[100], SquareFreeQ]
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PROG
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(PARI) forprime(p=1, 500, if(issquarefree(primepi(p)), print1(p, ", "))) \\ Felix Fröhlich, Apr 10 2018
(PARI) list(lim)=my(v=List(), k); forprime(p=2, lim\1, if(issquarefree(k++), listput(v, p))); Vec(v) \\ Charles R Greathouse IV, Aug 03 2023
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CROSSREFS
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Cf. A000040, A000961, A001222, A005117, A007097, A056239, A063834, A275024, A281113, A302242, A302478.
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KEYWORD
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nonn,easy
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AUTHOR
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STATUS
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approved
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