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 A085971 Union of primes and numbers that are not prime powers (A000040, A024619). 6
 2, 3, 5, 6, 7, 10, 11, 12, 13, 14, 15, 17, 18, 19, 20, 21, 22, 23, 24, 26, 28, 29, 30, 31, 33, 34, 35, 36, 37, 38, 39, 40, 41, 42, 43, 44, 45, 46, 47, 48, 50, 51, 52, 53, 54, 55, 56, 57, 58, 59, 60, 61, 62, 63, 65, 66, 67, 68, 69, 70, 71, 72, 73, 74, 75, 76, 77, 78 (list; graph; refs; listen; history; text; internal format)
 OFFSET 1,1 COMMENTS Complement of A025475; A085972(n) = Max{k: a(k)<=n}; different from A007916 and A052485, as a(28)=36; A085818(a(n)) = A000040(n). LINKS FORMULA a(n) = n + o(sqrt n). - Charles R Greathouse IV, Oct 19 2015 MATHEMATICA With[{nn=100}, Union[Join[Prime[Range[PrimePi[nn]]], DeleteCases[Range[2, 80], _?(PrimePowerQ[#]&)]]]] (* Harvey P. Dale, May 15 2019 *) PROG (PARI) is(n)=isprimepower(n)<2 && n>1 \\ Charles R Greathouse IV, Oct 19 2015 CROSSREFS Sequence in context: A089105 A028769 A094784 * A175082 A007916 A052485 Adjacent sequences:  A085968 A085969 A085970 * A085972 A085973 A085974 KEYWORD nonn,easy AUTHOR Reinhard Zumkeller, Jul 06 2003 STATUS approved

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Last modified January 21 18:52 EST 2021. Contains 340352 sequences. (Running on oeis4.)