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%I #10 Mar 12 2017 16:27:37
%S 2,1,3,4,1,11,3,2,1,1,1,23,2,5,3,1,1,27,1,5,1,1,1,73,1,1,1,7,1,25,5,2,
%T 1,1,1,71,1,2,3,13,1,71,1,2,1,1,1,73,1,1,1,1,1,9,1,23,5,1,1,29,1,5,3,
%U 1,1,1,1,2
%N a(n) is the smallest k such that there is no x with sigma(x) = k*n.
%H Charles R Greathouse IV, <a href="/A283524/b283524.txt">Table of n, a(n) for n = 1..10000</a>
%o (PARI) do(x)=my(v=List(),u=vectorsmall(x\1),t,n); for(k=1,x, t=sigma(k); if(t<=x, u[t]=1)); while(1, forstep(k=n++,x,n, if(u[k]==0, listput(v,k/n); next(2))); return(Vec(v))) \\ _Charles R Greathouse IV_, Mar 12 2017
%Y Cf. A007369, A000203.
%K nonn
%O 1,1
%A _Juri-Stepan Gerasimov_, Mar 09 2017
%E Corrected and extended by _Charles R Greathouse IV_, Mar 12 2017
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