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Number of divisors d of n! such that d-1 is prime.
2

%I #5 Feb 22 2020 20:03:01

%S 0,0,2,6,9,18,29,43,66,101,187,257,470,717,1033,1293,2442,3168,6011,

%T 7911,11179,16888,32603,39587,53063,79742,97707,127679,246428,302205,

%U 585129,670409,923535,1385145,1813935,2099557,4091926,6142573,8416157

%N Number of divisors d of n! such that d-1 is prime.

%H Ray Chandler, <a href="/A156190/b156190.txt">Table of n, a(n) for n=1..42</a>

%F a(n) = A072627(A000142(n)).

%t Table[Count[Divisors[n!],_?(PrimeQ[#-1]&)],{n,40}] (* _Harvey P. Dale_, Feb 22 2020 *)

%Y Cf. A072627, A067847.

%K nonn

%O 1,3

%A _Ray Chandler_, Feb 05 2009