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 A063658 Numbers 1<=m<=n for which GCD(m,n) is divisible by a square greater than 1. 2
 0, 0, 0, 1, 0, 0, 0, 2, 1, 0, 0, 3, 0, 0, 0, 4, 0, 2, 0, 5, 0, 0, 0, 6, 1, 0, 3, 7, 0, 0, 0, 8, 0, 0, 0, 12, 0, 0, 0, 10, 0, 0, 0, 11, 5, 0, 0, 12, 1, 2, 0, 13, 0, 6, 0, 14, 0, 0, 0, 15, 0, 0, 7, 16, 0, 0, 0, 17, 0, 0, 0, 24, 0, 0, 3, 19, 0, 0, 0, 20, 9, 0, 0, 21, 0, 0, 0, 22, 0, 10, 0, 23, 0, 0, 0, 24 (list; graph; refs; listen; history; text; internal format)
 OFFSET 1,8 LINKS Harry J. Smith, Table of n, a(n) for n=1,...,2000 EXAMPLE For n=12 we find GCD(4,12), GCD(8,12) and GCD(12,12) divisible by 4, so a(12)=3. PROG (PARI) { for (n=1, 2000, a=0; for (m=2, n, if (!issquarefree(gcd(m, n)), a++)); write("b063658.txt", n, " ", a) ) } [From Harry J. Smith, Aug 27 2009] CROSSREFS a(n)=n-A063659(n) Sequence in context: A059220 A059431 A113263 * A209777 A132013 A128229 Adjacent sequences:  A063655 A063656 A063657 * A063659 A063660 A063661 KEYWORD nonn AUTHOR Floor van Lamoen (fvlamoen(AT)hotmail.com), Jul 24 2001 EXTENSIONS More terms from Larry Reeves (larryr(AT)acm.org), Vladeta Jovovic (vladeta(AT)eunet.rs) and Dean Hickerson, Jul 26 2001 STATUS approved

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