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%I #14 Jun 03 2022 03:20:42
%S 2,5,6,12,6,11,14,24,18,17,14,28,20,15,23,25,22,45,24,26,31,30,30,38,
%T 48,41,54,39,38,46,42,68,35,53,42,117,74,54,60,58,44,62,86,60,90,51,
%U 62,75,74,80,55,97,85,56,66,87,79,88,87,78,75,69,103,192,78,70,134,82,77
%N Smallest k>n such that sigma(n) divides sigma(k).
%H Ivan Neretin, <a href="/A069789/b069789.txt">Table of n, a(n) for n = 1..10000</a>
%t a[n_] := Module[{k = n+1, s = DivisorSigma[1, n]}, While[!Divisible[DivisorSigma[1, k], s], k++]; k]; Array[a, 100] (* _Amiram Eldar_, Jun 03 2022 *)
%o (PARI) for(s=1,80,n=s+1; while(frac(sigma(n)/sigma(s))>0,n++); print1(n,","); )
%Y Cf. A000203.
%K easy,nonn
%O 1,1
%A _Benoit Cloitre_, May 01 2002