cp's OEIS Frontend

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.

A354106 Numbers k for which A354102(k) = A354102(sigma(k)).

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%I A354106 #16 May 24 2022 16:31:33
%S A354106 1,24,2475,2520,2728,5347,6683,8184,8307,8568,9108,9306,10106,11484,
%T A354106 12974,16041,17892,20049,23265,25265,26199,30318,32256,32435,38922,
%U A354106 39618,40918,44010,44576,44872,50976,55224,55720,56516,58817,63720,63952,64890,65689,66528,67356,69860,72072,73409,74448,75795,79101,83160
%N A354106 Numbers k for which A354102(k) = A354102(sigma(k)).
%C A354106 No common terms with A006872 in range a(2) .. a(1001).
%C A354106 Among the 1001 initial terms, only 3119744 and 13890816 occur also in A191217.
%H A354106 Antti Karttunen, <a href="/A354106/b354106.txt">Table of n, a(n) for n = 1..1001</a>
%H A354106 <a href="/index/O#opnseqs">Index entries for sequences where odd perfect numbers must occur, if they exist at all</a>
%H A354106 <a href="/index/Si#SIGMAN">Index entries for sequences related to sigma(n)</a>
%o A354106 (PARI)
%o A354106 \\ Needs also the program from A267099:
%o A354106 A354102(n) = eulerphi(A267099(n));
%o A354106 isA354106(k) = (A354102(k)==A354102(sigma(k)));
%Y A354106 Cf. A000010, A000203, A354102.
%Y A354106 Cf. also A006872, A191217, A354189, A354362.
%K A354106 nonn
%O A354106 1,2
%A A354106 _Antti Karttunen_, May 18 2022