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%I #3 Oct 21 2011 17:47:40
%S 1,2,5,10,17,31,71,137
%N Number of prime factors of the smallest n-perfect number.
%C Multiperfect numbers
%H Achim Flammenkamp, <a href="http://wwwhomes.uni-bielefeld.de/achim/mpn.html">The Multiply Perfect Numbers Page</a>.
%F a(n) = A001222(A007539(n))
%e a(4)=10 because the smallest 4-perfect number factorization is 2^5*3^3*5*7 which has 10 prime factors.
%Y Cf. A107481
%K hard,more,nonn
%O 1,2
%A Jose Brox (tautocrona(AT)terra.es), May 27 2005