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%I #8 Dec 05 2013 19:57:00
%S 9,99,998,9999,99999,999997,9999999,99999999,999999998,9999999999,
%T 99999999999,999999999997,9999999999999,99999999999999,
%U 999999999999998,9999999999999999,99999999999999999,999999999999999997
%N Largest n-digit number coprime to n.
%C a(286) = 10^286 - 5 is the first term with a(n) < 10^n - 3. - Rick L. Shepherd
%t f[n_] := Block[{k=10^n-1}, While[ GCD[n, k]>1, k-- ]; k]; Table[ f[n], {n, 18}] (* _Robert G. Wilson v_ *)
%o (PARI) for(n=1,300,m=10^n-1;while(gcd(m,n)>1,m--);print1(m,",")) (Rick L. Shepherd)
%K base,easy,nonn
%O 1,1
%A _Amarnath Murthy_, Jul 19 2005
%E More terms from _Rick L. Shepherd_ and _Robert G. Wilson v_, Jul 21 2005