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Prime factorials divided by their corresponding primorials.
7

%I #33 Aug 15 2015 06:35:14

%S 1,1,4,24,17280,207360,696729600,12541132800,115880067072000,

%T 1366643159020339200000,40999294770610176000000,

%U 1854768736099424576471040000000,109950690675973888893203251200000000

%N Prime factorials divided by their corresponding primorials.

%F p!/p# = A039716/A002110.

%F Partial products of A061214. - _Lekraj Beedassy_, Nov 06 2006

%F From _Chayim Lowen_, Jul 23 - Aug 05 2015: (Start)

%F a(n) = A036691(A065890(n)).

%F a(n) = A000142(A002808(A065890(n)))/A034386(A002808(A065890(n))).

%F a(n) = Product_{k=1..n} prime(k)^(A085604(prime(n),k)-1).

%F a(n) = A049614(prime(n)).

%F a(n) = Product_{k=1..prime(n)} k^A066247(k). (End)

%e E.g., 2 factorial divided by 2 primorial is 1; 3 factorial is 6, divided by 3 primorial (3*2=6) is also 1; 5 factorial is 120, divided by 5 primorial (5*3*2=30) is 4 and so forth.

%t Table[ Prime[n]! / Times @@ Prime[ Range[ n]], {n, 13}] (* _Robert G. Wilson v_, Mar 25 2004 *)

%o (PARI) a(n)=prime(n)!/prod(i=1,n,prime(i)) \\ _Ralf Stephan_, Dec 21 2013

%Y Subsequence of A036691. - _Chayim Lowen_, Jul 23 2015

%Y Cf. A002110, A039716.

%K nonn

%O 1,3

%A Don Willard (dwillard(AT)prairie.cc.il.us), Mar 23 2004

%E Edited by _Robert G. Wilson v_, Mar 25 2004