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%I #9 Jan 11 2020 03:09:06
%S 2,4,12,41,173,679,2806,11221,46200,195762,797388,3338052,13821332,
%T 56256665,230808795
%N Index of primorial(n) in A090958.
%C Significance: a(n+1)-1 is the count of numbers < primorial(n+1) whose largest prime divisor is <= prime(n). E.g., a(5) = 39 is the index of 210=2*3*5*7 in A090958, which means there are 38 numbers of the form 2^a*3^b*5^c < 210. Can someone derive a general formula (asymptotic)?
%Y Cf. A090958.
%K more,nonn
%O 1,1
%A _Amarnath Murthy_, Dec 31 2003
%E Corrected and extended by _David Wasserman_, Feb 23 2006