OFFSET
1,3
FORMULA
Partial products of A061214. - Lekraj Beedassy, Nov 06 2006
From Chayim Lowen, Jul 23 - Aug 05 2015: (Start)
a(n) = Product_{k=1..n} prime(k)^(A085604(prime(n),k)-1).
a(n) = A049614(prime(n)).
a(n) = Product_{k=1..prime(n)} k^A066247(k). (End)
EXAMPLE
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.
MATHEMATICA
Table[ Prime[n]! / Times @@ Prime[ Range[ n]], {n, 13}] (* Robert G. Wilson v, Mar 25 2004 *)
PROG
(PARI) a(n)=prime(n)!/prod(i=1, n, prime(i)) \\ Ralf Stephan, Dec 21 2013
CROSSREFS
KEYWORD
nonn
AUTHOR
Don Willard (dwillard(AT)prairie.cc.il.us), Mar 23 2004
EXTENSIONS
Edited by Robert G. Wilson v, Mar 25 2004
STATUS
approved