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 A087270 Solutions to gcd(x,pi(x)) = gcd(x, A000720(x)) > 1. Numbers x such that x and pi(x) have common divisor larger than one. 0
 4, 6, 8, 10, 14, 15, 16, 20, 22, 24, 27, 30, 33, 38, 39, 40, 44, 46, 48, 50, 51, 54, 56, 58, 62, 63, 64, 66, 72, 75, 77, 78, 80, 82, 90, 92, 93, 94, 96, 100, 102, 105, 108, 114, 115, 116, 117, 118, 120, 122, 123, 124, 125, 126, 132, 134, 136, 138, 140, 142, 144, 146 (list; graph; refs; listen; history; text; internal format)
 OFFSET 1,1 LINKS Table of n, a(n) for n=1..62. MATHEMATICA t=Table[GCD[w, PrimePi[w]], {w, 1, 1000}]; Flatten[Position[Sign[t-1], 1]] CROSSREFS Cf. A007053, A000720, A087266-A087269, A057809. Sequence in context: A084808 A310660 A031020 * A316262 A075124 A067315 Adjacent sequences: A087267 A087268 A087269 * A087271 A087272 A087273 KEYWORD nonn AUTHOR Labos Elemer, Sep 16 2003 STATUS approved

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Last modified April 16 18:22 EDT 2024. Contains 371750 sequences. (Running on oeis4.)