%I #12 Apr 27 2017 12:00:52
%S 0,2,27,165,734,3109,11568,40820,137850,457191
%N Number of quasi-Carmichael numbers less than 10^n.
%C For quasi-Carmichael numbers see A257750.
%e a(1) = 0 because there are no quasi-Carmichael numbers below 10^1.
%e a(2) = 2 because there are two quasi-Carmichael numbers below 10^2, namely, 35 and 77.
%o (Perl) use ntheory ":all"; my($s,$e)=(0,1); forcomposites { say $e++," $s" if $_ >= 10**$e; $s++ if is_quasi_carmichael($_) } 1e7; # _Dana Jacobsen_, Apr 27 2017
%Y Cf. A055553, A216929, A257750.
%K nonn,more,hard
%O 1,2
%A _Tim Johannes Ohrtmann_, Oct 30 2015
%E a(8)-a(10) from _Dana Jacobsen_, Apr 27 2017
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