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 A175843 a(n) = (10^n)-th odd squarefree number. 0
 1, 21, 241, 2463, 24671, 246745, 2467401, 24674017, 246740209, 2467401073, 24674011069, 246740110021, 2467401100859, 24674011004865, 246740110026451, 2467401100272455, 24674011002722867, 246740110027242491, 2467401100272345957 (list; graph; refs; listen; history; text; internal format)
 OFFSET 0,2 LINKS FORMULA a(n) ~ (pi/2)^2 * 10^n + O(10^(n/2)). This follows from the formula given in A056911: A056911(n) ~ n * (3/2) * zeta(2) + O(n^(1/2)) = n * (3/2) * (pi^2 / 6) + O(n^(1/2)). - M. F. Hasler CROSSREFS Cf. A056911. Sequence in context: A316426 A317428 A089937 * A198974 A271792 A177730 Adjacent sequences:  A175840 A175841 A175842 * A175844 A175845 A175846 KEYWORD nonn AUTHOR Zak Seidov, Sep 24 2010 EXTENSIONS a(10)-a(18) from Max Alekseyev, Sep 24 2010 Edited by N. J. A. Sloane, Sep 24 2010 STATUS approved

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Last modified May 21 19:42 EDT 2022. Contains 353929 sequences. (Running on oeis4.)