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This is a front-end for the Online Encyclopedia of Integer Sequences, made by Christian Perfect. The idea is to provide OEIS entries in non-ancient HTML, and then to think about how they're presented visually. The source code is on GitHub.

A354711 Numbers k such that the number of divisors of k divides k-1.

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%I A354711 #14 Jun 04 2022 09:42:22
%S A354711 1,3,4,5,7,11,13,16,17,19,21,23,25,29,31,33,37,41,43,47,49,53,57,59,
%T A354711 61,64,65,67,69,71,73,77,79,81,83,85,89,93,97,100,101,103,105,107,109,
%U A354711 113,121,125,127,129,131,133,137,139,141,145,149,151,157,161,163,167,169,173,175,177,179,181
%N A354711 Numbers k such that the number of divisors of k divides k-1.
%C A354711 Numbers k such that k == 1 (mod A000005(k)).
%C A354711 Every odd prime is a term. Nonprime terms are listed in A354712.
%t A354711 Select[Range[200], Divisible[# - 1, DivisorSigma[0, #]] &] (* _Amiram Eldar_, Jun 03 2022 *)
%Y A354711 Cf. A000005, A033950, A272872, A354712, A354714, A354715, A354716.
%K A354711 nonn
%O A354711 1,2
%A A354711 _Max Alekseyev_, Jun 03 2022