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 A122906 Numbers n such that in Z/nZ the number of squares is less than or equal to the number of invertible elements. 5
 1, 3, 4, 5, 7, 8, 9, 11, 12, 13, 15, 16, 17, 19, 20, 21, 23, 24, 25, 27, 28, 29, 31, 32, 33, 35, 36, 37, 39, 40, 41, 43, 44, 45, 47, 48, 49, 51, 52, 53, 55, 56, 57, 59, 60, 61, 63, 64, 65, 67, 68, 69, 70, 71, 72, 73, 75, 76, 77, 79, 80, 81, 83, 84, 85, 87, 88, 89, 90, 91, 92, 93 (list; graph; refs; listen; history; text; internal format)
 OFFSET 1,2 COMMENTS The terms 70 and 90 show that sequence is strictly different from A042965. - Andrew Plewe, Jun 13 2007 LINKS Ivan Neretin, Table of n, a(n) for n = 1..10000 FORMULA Numbers n such that A000224(n) <= A000010(n). Union of A122903 and A122904. Complement of A122905 in positive integers. MATHEMATICA Select[Range@94, Length@Union@Mod[Range[#]^2, #] <= EulerPhi[#] &] (* Ivan Neretin, Dec 14 2016 *) CROSSREFS Cf. A122903, A122904, A122905, A122907. Sequence in context: A284679 A183147 A074227 * A042965 A260003 A005848 Adjacent sequences:  A122903 A122904 A122905 * A122907 A122908 A122909 KEYWORD nonn AUTHOR Max Alekseyev, Sep 18 2006 STATUS approved

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