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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
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refs;
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OFFSET
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1,1
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COMMENTS
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All odd squares (A016754) are present, but not all terms are squares. A348743 gives the nonsquare terms.
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LINKS
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Table of n, a(n) for n=1..56.
Index entries for sequences related to sigma(n)
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MATHEMATICA
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odd[n_] := n/2^IntegerExponent[n, 2]; Select[Range[1, 10^4, 2], odd[DivisorSigma[1, #]] > # &] (* Amiram Eldar, Nov 02 2021 *)
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PROG
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(PARI)
A000265(n) = (n >> valuation(n, 2));
isA348742(n) = ((n%2)&&A000265(sigma(n))>n);
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CROSSREFS
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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
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KEYWORD
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nonn
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AUTHOR
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Antti Karttunen, Nov 02 2021
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STATUS
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approved
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