# Greetings from The On-Line Encyclopedia of Integer Sequences! http://oeis.org/ Search: id:a119644 Showing 1-1 of 1 %I A119644 #7 Apr 09 2014 10:15:51 %S A119644 3,7,7,11,17,19,23,29,29,37,41,43,47,53,53,61,61,71,79,73,83,89,97, %T A119644 101,103,107,109,127,127,131,137,139,139,151,157,163,167,173,179,181, %U A119644 191,197,197,199,199,223,229,229,233,241,241,251,257,263,269,277,277,277 %N A119644 a(n) = n-th prime from among those primes which are coprime to the n-th composite. %e A119644 8 is the 3rd composite. 3,5,7,11,... is the sequence of primes which are coprime to 8. 7 is the 3rd term of these primes, so a(3) = 7. %o A119644 (PARI) {m=60;c=1;for(n=1,m,c++;while(isprime(c),c++);q=2;k=n;while(k>0,p=q;if(gcd(p,c)==1,k--);q=nextprime(p+1));print1(p,","))} - (Klaus Brockhaus, Aug 15 2006) %K A119644 nonn %O A119644 1,1 %A A119644 _Leroy Quet_, Aug 04 2006 %E A119644 More terms from _Klaus Brockhaus_, Aug 15 2006 # Content is available under The OEIS End-User License Agreement: http://oeis.org/LICENSE