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%I #12 Mar 31 2012 13:22:05
%S 1,2,12,180,27720,122522400,130429015516800,1970992304700453905270400,
%T 1897544233056092162003806758651798777216000,
%U 4368924363354820808981210203132513655327781713900627249499856876120704000
%N a(n) = least number m such that sigma(m)/m > n, where sigma(m) = sum of divisors of m.
%e Values written as products of primorials:
%e n a(n)
%e 0 1
%e 1 2
%e 2 2*3#
%e 3 3#*5# (= 180)
%e 4 2*3#*11#
%e 5 8*5#*17#
%e 6 16*3#*7#*29#
%e 7 8*3#*3#*7#*53#
%e 8 32*3#*3#*5#*11#*89#
%e 9 32*3#*3#*7#*17#*157#
%e 10 16*3#*3#*5#*7#*23#*271#
%e 11 16*3#*3#*5#*7#*29#*487#
%e 12 16*3#*3#*5#*7#*13#*31#*857#
%Y Cf. A023199 (least k with sigma(k) >= nk)
%K nonn
%O 0,2
%A _Pierre CAMI_, Jan 27 2008, corrected Feb 26 2008 with the help of Emeric Deutsch
%E More terms can be obtained by expanding the expressions in the example lines. - _N. J. A. Sloane_, Feb 26 2008
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