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%I #10 Dec 29 2013 12:50:45
%S 1,9,38423,104855,247863,313929,345807,376095,469623,623615,787127,
%T 943695,985369,1606281,1754039,1933815,2034423,2181409,3043401,
%U 5147241,5545617,5612535,6385703,7084143,8868321,10606679,11470511,11954409,12276745,12794655,13213921,14142695,15512065,15737953,15786351,16844135
%N Odd numbers n such that sigma(sigma(n^2)) is odd.
%C The sum of divisors of a square is always odd, therefore these numbers have the property that x=n^2, y=sigma(x) and z=sigma(y) are all three odd.
%C This is the subsequence of odd terms of A008847.
%H M. F. Hasler, <a href="/A234641/b234641.txt">Table of n, a(n) for n = 1..122</a>
%Y Cf. A000203, A000290, A008848, A163763.
%K nonn
%O 1,2
%A _M. F. Hasler_, Dec 28 2013