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A054270
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Largest prime below prime(n)^2 (A001248).
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8
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3, 7, 23, 47, 113, 167, 283, 359, 523, 839, 953, 1367, 1669, 1847, 2207, 2803, 3469, 3719, 4483, 5039, 5323, 6229, 6883, 7919, 9403, 10193, 10607, 11447, 11867, 12763, 16127, 17159, 18757, 19319, 22193, 22787, 24631, 26561, 27883, 29927, 32029
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OFFSET
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1,1
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COMMENTS
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For n > 1, the n-1 first primes determine the primes up to a(n). This is how the Sieve of Eratosthenes works. - Jean-Christophe Hervé, Oct 21 2013
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LINKS
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FORMULA
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a(n) = Max[prime q: q < prime(n)^2].
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MAPLE
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seq(prevprime(ithprime(i)^2), i=1..100); # Robert Israel, May 04 2020
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MATHEMATICA
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PROG
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(PARI) a(n) = precprime(prime(n)^2); \\ Michel Marcus, Dec 13 2013
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CROSSREFS
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KEYWORD
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nonn
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AUTHOR
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STATUS
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approved
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