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%I #12 Aug 12 2015 17:16:28
%S 2,3,4,5,6,2,8,3,10,4,12,5,2,6,16,3,18,8,4,9,22,2,24,11,6,3,28,7,30,4,
%T 8,15,2,5,36,17,10,3,40,11,42,7,4,21,46,2,48,5,14,9,52,3,6,10,16,27,
%U 58,4,60,29,2,12,8,5,66,13,20,3,70,6,72,35,10,15,4,7,78,2,24,39,82,5
%N Smallest difference > 1 between d and n/d for any divisor d of n.
%C a(p) = p-1 for prime p.
%H Robert Israel, <a href="/A082120/b082120.txt">Table of n, a(n) for n = 3..10000</a>
%p F:= proc(n) local p;
%p p:= min(select(t -> t - n/t > 1, numtheory:-divisors(n)));
%p p - n/p
%p end proc:
%p map(F, [$3..100]); # _Robert Israel_, Aug 12 2015
%t sd[n_]:=Min[Select[Abs[#-n/#]&/@Divisors[n],#>1&]]; Array[sd,90,3] (* _Harvey P. Dale_, Sep 28 2013 *)
%o (PARI) for(n=3, 100, v=divisors(n); r=sqrt(n); t=0; for(k=1, length(v), if(v[k]>=r, t=k; break)); if(v[t]^2==n, u=t, u=t-1); if(v[t]-v[u]<2, u=u-1; t=t+1); print1(v[t]-v[u]", "))
%Y Cf. A082119, A056737, A003681, A082121.
%K nonn,easy
%O 3,1
%A _Ralf Stephan_, Apr 04 2003
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