%I #13 Aug 18 2014 07:58:55

%S 1,2,8,24,144,720,5760,51840,518400,3628800,43545600,479001600,

%T 6706022400,100590336000,1609445376000,20922789888000,376610217984000,

%U 6402373705728000,128047474114560000,2688996956405760000,59157933040926720000,1124000727777607680000,26976017466662584320000,674400436666564608000000

%N Least number k such that n!/k is prime.

%H Jens Kruse Andersen, <a href="/A242456/b242456.txt">Table of n, a(n) for n = 2..1000</a>

%F a(n) = n!/prime(pi(n)) = A000142(n)/A007917(n) for n > 1.

%p with(numtheory): A242456:=n->n!/ithprime(pi(n)): seq(A242456(n), n=2..30); # _Wesley Ivan Hurt_, Aug 17 2014

%t Table[n!/Prime[PrimePi[n]], {n, 2, 30}] (* _Wesley Ivan Hurt_, Aug 17 2014 *)

%o (PARI)

%o vector(50,n,(n+1)!/(prime(primepi(n+1))))

%Y Cf. A000142, A007917.

%K nonn,easy

%O 2,2

%A _Derek Orr_, Aug 16 2014