A073838 - OEIS

A073838

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

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

(list; graph; refs; listen; history; text; internal format)

OFFSET

1,1

COMMENTS

a(n) = A034386(2*n)/A034386(n-1); A179214(n) <= a(n). - Reinhard Zumkeller, Jul 05 2010

LINKS

T. D. Noe, Table of n, a(n) for n = 1..500

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

Adjacent sequences: A073835 A073836 A073837 * A073839 A073840 A073841

KEYWORD

nonn

AUTHOR

Amarnath Murthy and Benoit Cloitre, Aug 12 2002

EXTENSIONS

More terms from Sascha Kurz, Aug 14 2002

Missing a(29) inserted by Andrew Howroyd, Feb 23 2018

STATUS

approved