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%I #16 Mar 17 2024 02:12:21
%S 120,672,30240,32760,523776,2178540,23569920,45532800,142990848,
%T 459818240,1379454720,1476304896,14182439040,31998395520,43861478400,
%U 51001180160,66433720320,153003540480,403031236608,518666803200
%N Multiply perfect numbers k such that sigma(k)/k > 2.
%C Subsequence of multiply perfect numbers (A007691). Numbers k = A007691(n) such that sigma(A007691(n))/A007691(n) > 2. Numbers k = A007691(n) such that A054030(n) > 2.
%H Charles R Greathouse IV, <a href="/A166069/b166069.txt">Table of n, a(n) for n=1..1587</a>
%H Achim Flammenkamp, <a href="http://wwwhomes.uni-bielefeld.de/achim/mpn.html">The Multiply Perfect Numbers Page</a>
%e For n = 1 the a(1) = 120, sigma(120) / 120 = 360 / 120 = 3, i.e. > 2.
%o (PARI) isok(n) = sn = sigma(n)/n ; (type(sn) == "t_INT") && (sn > 2); \\ _Michel Marcus_, Oct 24 2013
%K nonn
%O 1,1
%A _Jaroslav Krizek_, Oct 06 2009
%E Extended by _Charles R Greathouse IV_, Oct 12 2009
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