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%I #12 Apr 11 2024 04:08:15
%S 295,590,767,885,1038,1416,1534,1589,1770,2065,2301,2422,3178,3186,
%T 3245,3304,3448,3540,4130,4602,4767,5192,5230,5448,5516,5605,6195,
%U 6291,6356,6490,6574,6860,7266,7945,7965,8236,8260,8437,8968,9145,9204,9342
%N Non-balanced numbers in A015765.
%H Amiram Eldar, <a href="/A074868/b074868.txt">Table of n, a(n) for n = 1..10000</a>
%F sigma_7(a(n)) mod phi(a(n)) = 0; sigma(a(n)) mod phi(a(n)) <> 0.
%t q[n_] := Sign[Mod[DivisorSigma[{1, 7}, n], EulerPhi[n]]] == {1, 0}; Select[Range[10000], q] (* _Amiram Eldar_, Apr 11 2024 *)
%o (PARI) is(n) = {my(f = factor(n), phi = eulerphi(f)); (sigma(f) % phi) && !(sigma(f, 7) % phi);} \\ _Amiram Eldar_, Apr 11 2024
%Y Cf. A000010, A000203, A013955, A015765, A020492, A078539.
%Y Cf. A074866, A077801, A077803, A078544, A078549, A078550.
%K nonn,changed
%O 1,1
%A _Labos Elemer_, Dec 05 2002
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