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%I #17 Jan 31 2015 09:55:53
%S 15,27,57,135,345,927,2577,7335,21225,62127,183297,543735,1618905,
%T 4832127,14447217,43243335,129533385,388206927,1163834337,3489930135,
%U 10466644665,31393642527,94168344657,282479868135
%N Least number m such that the number of numbers k <= m with k > spf(k)^n exceeds the number of numbers with k <= spf(k)^n.
%C m<a(n): #{k: k>spf(k)^n & 1<=k<=m} <= m/2;
%C m>=a(n): #{k: k>spf(k)^n & 1<=k<=m} > m/2.
%F Numbers so far satisfy a(n) = 3^n + 3*2^n + 6. - _Ralf Stephan_, May 10 2004
%F Empirical G.f.: 3*x*(5-21*x+20*x^2)/(1-x)/(1-2*x)/(1-3*x)). [_Colin Barker_, Feb 22 2012]
%Y Cf. A088382, A088382, A088380, A088381, A000430, A080257.
%K nonn
%O 1,1
%A _Reinhard Zumkeller_, Sep 29 2003
%E a(14)-a(24) from _Giovanni Resta_, May 23 2013
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