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 A323024 Numbers with exactly three distinct exponents in their prime factorization, or three distinct parts in their prime signature. 9
 360, 504, 540, 600, 720, 756, 792, 936, 1008, 1176, 1188, 1200, 1224, 1350, 1368, 1400, 1404, 1440, 1500, 1584, 1620, 1656, 1836, 1872, 1960, 2016, 2052, 2088, 2160, 2200, 2232, 2250, 2268, 2352, 2400, 2448, 2484, 2520, 2600, 2646, 2664, 2736, 2800, 2880, 2904 (list; graph; refs; listen; history; text; internal format)
 OFFSET 1,1 COMMENTS Positions of 3's in A071625. Numbers k such that A001221(A181819(k)) = 3. The asymptotic density of this sequence is (6/Pi^2) * Sum_{n>=2, n squarefree} r(n)/((n-1)*psi(n)) = 0.030575..., where psi is the Dedekind psi function (A001615), and r(n) = Sum_{d|n, 1

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Last modified May 18 22:55 EDT 2021. Contains 344006 sequences. (Running on oeis4.)