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%I #11 Dec 12 2024 15:12:48
%S 2,2,3,2,2,3,2,2,3,2,2,4,2,2,3,2,2,3,2,2,3,2,2,4,2,2,3,2,2,3,2,2,3,2,
%T 2,4,2,2,3,2,2,3,2,2,3,2,2,4,2,2,3,2,2,3,2,2,3,2,2,4,2,2,3,2,2,3,2,2,
%U 3,2,2,4,2,2,3,2,2,3,2,2,3,2,2,7,2,2,3,2,2,3
%N Smallest positive m such that sigma(m) does not divide n, where sigma is the sum-of-divisors function (A000203).
%H Paolo Xausa, <a href="/A378914/b378914.txt">Table of n, a(n) for n = 1..10000</a>
%H <a href="/index/Si#SIGMAN">Index entries for sequences related to sigma(n)</a>
%t A378914[n_] := Module[{m = 1}, While[Divisible[n, DivisorSigma[1,++m]]]; m];
%t Array[A378914, 100]
%o (PARI) a(n) = my(m=1); while (!(n % sigma(m)), m++); m; \\ _Michel Marcus_, Dec 11 2024
%Y Cf. A000203, A051549, A378912.
%K nonn,easy,new
%O 1,1
%A _Paolo Xausa_, Dec 11 2024