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A073838 Product of primes p satisfying n <= p <= 2n. 7

%I #19 Feb 23 2018 15:33:51

%S 2,6,15,35,35,77,1001,143,2431,46189,46189,96577,96577,7429,215441,

%T 6678671,6678671,392863,14535931,765049,31367009,1348781387,

%U 1348781387,2756205443,2756205443,2756205443,146078888479,146078888479,146078888479,297194980009

%N Product of primes p satisfying n <= p <= 2n.

%C a(n) = A034386(2*n)/A034386(n-1); A179214(n) <= a(n). - _Reinhard Zumkeller_, Jul 05 2010

%H T. D. Noe, <a href="/A073838/b073838.txt">Table of n, a(n) for n = 1..500</a>

%e a(7) = 1001 = 7*11*13 (product of primes between 7 and 14).

%p 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);

%t Table[Times @@ Select[Range[n, 2 n], PrimeQ], {n, 28}] (* _Jayanta Basu_, Aug 12 2013 *)

%o (PARI) a(n)=prod(i=n,2*n,i^isprime(i))

%Y Cf. A073837.

%K nonn

%O 1,1

%A _Amarnath Murthy_ and _Benoit Cloitre_, Aug 12 2002

%E More terms from _Sascha Kurz_, Aug 14 2002

%E Missing a(29) inserted by _Andrew Howroyd_, Feb 23 2018

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Last modified April 25 09:23 EDT 2024. Contains 371967 sequences. (Running on oeis4.)