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Minimal numbers with the same values for sigma_0(n) and sigma(n) as one or more other numbers.
5

%I #3 Mar 30 2012 17:35:23

%S 14,33,46,62,87,54,94,66,123,118,141,142,102,158,114,166,213,138,214,

%T 249,182,132,267,174,254,186,303,278,321,230,244,302,395,248,334,246,

%U 204,393,358,382,282,485,398,553,535,318,446,429,276,454,478,354,264

%N Minimal numbers with the same values for sigma_0(n) and sigma(n) as one or more other numbers.

%C Numbers n such that for some m > n, sigma(n) = sigma(m) and sigma_0(n) = sigma_0(m), but this does hold for any m < n.

%C Values are sorted by sigma(n), then by sigma_0(n).

%C See the a-file for a PARI program and more values.

%H Franklin T. Adams-Watters, <a href="/A162279/a162279.txt">Table of duplicate sigma values up to sigma(n) = 10000</a>

%e sigma(14) = sigma(15) = 24, sigma_0(14) = sigma_0(15) = 4, so 14 is in the sequence. sigma(16) = sigma(25) = 31, but sigma_0(16) = 5 != sigma_0(25) = 3, so 16 is not in the sequence.

%Y Cf. A000005, A000203, A162280, A162281, A162282, A162283.

%K nonn

%O 1,1

%A _Franklin T. Adams-Watters_, Jun 29 2009