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A085962
Numerators of Farey fractions with prime numerators and denominators.
0
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, 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, 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
OFFSET
3,1
PROG
(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) }
CROSSREFS
Cf. A085693.
Sequence in context: A375431 A334216 A100549 * A160821 A300225 A060244
KEYWORD
easy,nonn,frac
AUTHOR
Cino Hilliard, Aug 17 2003
STATUS
approved