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 A348742 Odd numbers k for which A161942(k) > k, where A161942 is the odd part of sigma. 5
 9, 25, 49, 81, 121, 169, 225, 289, 361, 441, 529, 625, 729, 841, 961, 1089, 1225, 1369, 1521, 1681, 1849, 2025, 2205, 2209, 2401, 2601, 2809, 3025, 3249, 3481, 3721, 3969, 4225, 4489, 4761, 5041, 5329, 5625, 5929, 6241, 6561, 6889, 7225, 7569, 7921, 8281, 8649, 9025, 9409, 9801, 10201, 10609, 11025, 11449, 11881, 12321 (list; graph; refs; listen; history; text; internal format)
 OFFSET 1,1 COMMENTS All odd squares (A016754) are present, but not all terms are squares. A348743 gives the nonsquare terms. LINKS MATHEMATICA odd[n_] := n/2^IntegerExponent[n, 2]; Select[Range[1, 10^4, 2], odd[DivisorSigma[1, #]] > # &] (* Amiram Eldar, Nov 02 2021 *) PROG (PARI) A000265(n) = (n >> valuation(n, 2)); isA348742(n) = ((n%2)&&A000265(sigma(n))>n); CROSSREFS Union of A016754 and A348743. Cf. A161942, A348741. Cf. also A348739. Sequence in context: A113659 A325701 A113745 * A016754 A110487 A259417 Adjacent sequences: A348739 A348740 A348741 * A348743 A348744 A348745 KEYWORD nonn AUTHOR Antti Karttunen, Nov 02 2021 STATUS approved

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Last modified March 28 14:02 EDT 2023. Contains 361595 sequences. (Running on oeis4.)