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 A087797 Primes, squares of primes and cubes of primes. 4
 2, 3, 4, 5, 7, 8, 9, 11, 13, 17, 19, 23, 25, 27, 29, 31, 37, 41, 43, 47, 49, 53, 59, 61, 67, 71, 73, 79, 83, 89, 97, 101, 103, 107, 109, 113, 121, 125, 127, 131, 137, 139, 149, 151, 157, 163, 167, 169, 173, 179, 181, 191, 193, 197, 199, 211, 223, 227, 229, 233, 239, 241 (list; graph; refs; listen; history; text; internal format)
 OFFSET 1,1 LINKS Vincenzo Librandi, Table of n, a(n) for n = 1..1000 FORMULA a(n) ~ n log n. - Charles R Greathouse IV, Oct 19 2015 MATHEMATICA m=400; Union[Prime[Range[PrimePi[m]]], Prime[Range[PrimePi[m^(1/2)]]]^2, Prime[Range[PrimePi[m^(1/3)]]]^3] (* Vladimir Joseph Stephan Orlovsky, Apr 11 2011 *) With[{nn=70}, Take[Union[Flatten[{#, #^2, #^3}&/@Prime[Range[nn]]]], nn]] (* Harvey P. Dale, Oct 16 2012 *) PROG (PARI) is(n)=my(t=isprimepower(n)); t && t<4 \\ Charles R Greathouse IV, Oct 19 2015 CROSSREFS Cf. A000430, A002760. Sequence in context: A283262 A115975 A277187 * A280619 A282136 A153730 Adjacent sequences:  A087794 A087795 A087796 * A087798 A087799 A087800 KEYWORD nonn AUTHOR Benoit Cloitre, Oct 10 2003 STATUS approved

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Last modified December 14 21:22 EST 2018. Contains 318138 sequences. (Running on oeis4.)