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.
%I A364565 #6 Jul 29 2023 15:58:54 %S A364565 1,2,3,4,5,6,8,10,12,16,20,24,32,40,48,64,80,85,96,128,160,170,192, %T A364565 256,320,340,384,512,640,680,768,1024,1280,1360,1536,2048,2560,2720, %U A364565 3072,4096,5120,5440,6144,8192,10240,10880,12288,16384,20480,21760,24576,32768,40960,43520,49152,65536,81920,87040,98304,131072 %N A364565 Numbers k at which point A364557 (the Möbius transform of A005941) is equal to A000010 (Euler phi function). %C A364565 Question: Are there any other odd terms apart from 1, 3, 5, 85? %o A364565 (PARI) %o A364565 A364557(n) = if(1==n, 1, 2^(primepi(vecmax(factor(n)[, 1]))+(bigomega(n)-omega(n))-1)); %o A364565 isA364565(n) = (A364557(n)==eulerphi(n)); %Y A364565 Positions of 0's in A364558. %Y A364565 Cf. A000010, A029747, A364557, A364566. %K A364565 nonn %O A364565 1,2 %A A364565 _Antti Karttunen_, Jul 29 2023