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%I #15 Jan 12 2022 14:01:50
%S 6,35,143,323,667,1147,1763,2491,3599,4757,5767,7387,9797,11021,12317,
%T 16637,19043,22499,25591,28891,32399,36863,39203,47053,51983,55687,
%U 60491,67591,72899,77837,82919,95477,99221,111547,121103,126727,136891
%N a(n) = prime(2*n-1)*prime(2*n).
%C a(n+1) is the smallest squarefree composite number that is relatively prime to the first 2*n prime numbers.
%C Bisection of A006094. - _R. J. Mathar_, Jan 23 2013
%H Michael De Vlieger, <a href="/A089581/b089581.txt">Table of n, a(n) for n = 1..10000</a>
%F prime(2*n-1)*prime(2*n), n=1, 2, 3 ...
%e a(13)=9797
%t Table[Prime[2 n - 1] Prime[2 n], {n, 30}] (* _Michael De Vlieger_, Jul 21 2016 *)
%t Times@@@Partition[Prime[Range[80]],2] (* _Harvey P. Dale_, Jan 12 2022 *)
%o (PARI) p=2;q=3;i=1;a=vector(100);for(i=1,100,a[i]=p*q;p=nextprime(q+1);q=nextprime(p+1));a
%K easy,nonn
%O 1,1
%A Norbert A'Campo (nac(AT)member.ams.org), Dec 29 2003
%E Edited by Zak Seidov, Jun 13 2006
%E Typo in PARI program fixed by _Zak Seidov_, May 19 2010
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