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A241716
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Primes p such that p^3 - 2 is semiprime.
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2
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2, 3, 5, 7, 11, 13, 17, 41, 43, 47, 61, 79, 89, 101, 107, 139, 157, 181, 199, 239, 271, 307, 311, 331, 337, 347, 349, 379, 397, 409, 421, 431, 479, 487, 499, 521, 523, 541, 571, 607, 613, 641, 643, 661, 673, 701, 719, 761, 769, 811, 823, 829, 839, 877, 881, 883
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OFFSET
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1,1
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LINKS
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EXAMPLE
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11 is prime and appears in the sequence because 11^3 - 2 = 1329 = 3 * 443, which is a semiprime.
17 is prime and appears in the sequence because 17^3 - 2 = 4911 = 3 * 1637, which is a semiprime.
23 is prime but does not appear in the sequence because 23^3 - 2 = 12165 = 3 * 5 * 811, which is not a semiprime.
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MAPLE
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with(numtheory):A241716:= proc() local k; k:=ithprime(x); if bigomega(k^3-2)=2 then RETURN (k); fi; end: seq(A241716(), x=1..500);
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MATHEMATICA
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Select[Prime[Range[200]], PrimeOmega[#^3-2]==2&] (* Harvey P. Dale, Dec 09 2018 *)
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CROSSREFS
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Cf. A001358, A063637, A063638, A072381, A082919, A145292, A228183, A237627, A241483, A241493, A241659.
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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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