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 A279984 Positions of the prime numbers in the sequence of numbers that are not perfect powers (A007916). 2
 1, 2, 3, 5, 7, 9, 12, 14, 18, 22, 24, 28, 32, 34, 38, 43, 49, 51, 56, 60, 62, 68, 71, 77, 85, 88, 90, 94, 96, 100, 112, 115, 121, 123, 132, 134, 140, 146, 150, 155, 161, 163, 173, 175, 178, 180, 192, 203, 206, 208, 212, 218, 220, 229, 234, 240, 246, 248, 254 (list; graph; refs; listen; history; text; internal format)
 OFFSET 1,2 LINKS John Cerkan, Table of n, a(n) for n = 1..10000 FORMULA A007916(a(n)) = A000040(n). MATHEMATICA nn=100; rads=Select[Range[2, nn], GCD@@FactorInteger[#][[All, 2]]===1&]; Table[Position[rads, Prime[n]][[1, 1]], {n, PrimePi[nn]}] PROG (PARI) lista(nn) = Vec(select(x->isprime(x), Vec(select(x->(!ispower(x)&&x>1), [1..nn])), 1)); \\ Michel Marcus, May 04 2018 CROSSREFS Cf. A000040, A007916, A279944. Sequence in context: A293262 A348623 A200049 * A184017 A024195 A071423 Adjacent sequences: A279981 A279982 A279983 * A279985 A279986 A279987 KEYWORD nonn AUTHOR Gus Wiseman, Dec 24 2016 STATUS approved

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Last modified September 16 19:27 EDT 2024. Contains 375977 sequences. (Running on oeis4.)