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A073838
Product of primes p satisfying n <= p <= 2n.
7
2, 6, 15, 35, 35, 77, 1001, 143, 2431, 46189, 46189, 96577, 96577, 7429, 215441, 6678671, 6678671, 392863, 14535931, 765049, 31367009, 1348781387, 1348781387, 2756205443, 2756205443, 2756205443, 146078888479, 146078888479, 146078888479, 297194980009
OFFSET
1,1
COMMENTS
a(n) = A034386(2*n)/A034386(n-1); A179214(n) <= a(n). - Reinhard Zumkeller, Jul 05 2010
EXAMPLE
a(7) = 1001 = 7*11*13 (product of primes between 7 and 14).
MAPLE
for n from 1 to 50 do l := 1:for j from n to 2*n do if isprime(j) then l := l*j:fi:od:a[n] := l:od:seq(a[j], j=1..50);
MATHEMATICA
Table[Times @@ Select[Range[n, 2 n], PrimeQ], {n, 28}] (* Jayanta Basu, Aug 12 2013 *)
PROG
(PARI) a(n)=prod(i=n, 2*n, i^isprime(i))
CROSSREFS
Cf. A073837.
Sequence in context: A338055 A336799 A340779 * A337646 A014303 A076060
KEYWORD
nonn
AUTHOR
EXTENSIONS
More terms from Sascha Kurz, Aug 14 2002
Missing a(29) inserted by Andrew Howroyd, Feb 23 2018
STATUS
approved