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%I #14 Mar 31 2012 10:23:01
%S 1,2,7,27,190,1621,17271,200536,2757881,47108763,843069901,17797435824
%N Number of numbers <= prime(n)# having n prime factors (with multiplicity), where prime(n)# = A002110(n) is the n-th primorial.
%C a(n) = A077618(A002110(n)), see A077621.
%e a(3)=7, as there are 7 numbers <= prime(3)# = 2*3*5 = 30 having 3 prime factors: 8=2*2*2, 12=2*2*3, 18=2*3*3, 20=2*2*5, 27=3*3*3, 28=2*2*7 and 30=2*3*5.
%Y Cf. A001222.
%K nonn
%O 1,2
%A _Reinhard Zumkeller_, Nov 12 2002
%E 17271 from _Sascha Kurz_, Jan 04 2003
%E a(8)-a(11) from _Donovan Johnson_, Nov 15 2009
%E a(12) from _Donovan Johnson_, Jul 16 2011