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%I #3 Oct 01 2013 17:57:41
%S 2,2,3,2,2,2,3,3,2,5,2,3,2,2,3,5,3,7,2,5,2,2,3,3,2,5,2,3,5,7,3,7,2,5,
%T 11,2,2,3,2,3,3,2,5,5,2,7,3,5,7,3,7,11,2,5,13,11,2,2,2,3,3,2,3,5,3,2,
%U 5,7,5,2,7,3,5,7,11,3,7,11,2,13,5,13,11,17,2,2,2,3,2,3,3,2,5,3,5,3,2,5,7,7,5
%N Numerators of Farey fractions with prime numerators and denominators.
%o (PARI) \ Farey sequence of order n fareyct(n) = { forprime(x=2,n, y = farey(x); \ print1(y","); ) } farey(n) = { c=0; m=n*(n-2)+2; a=vector(m); forprime(x=1,n, forprime(y=x,n, v = x/y; if(v<1, c++; a[c]=v; ) ) ); a = vecsort(a); c=0; for(x=2,m, if(a[x]<>a[x-1] & a[x]<>0, print1(numerator(a[x])","); c++; ) ); return(c) }
%Y Cf. A085693.
%K easy,nonn,frac
%O 3,1
%A _Cino Hilliard_, Aug 17 2003
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