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 A354098 #11 Dec 21 2023 10:22:35
%S A354098 1,6,8,12,14,16,18,20,22,24,28,32,36,38,40,44,46,48,52,54,56,60,62,64,
%T A354098 68,72,76,80,84,86,88,92,94,96,98,100,104,108,112,116,118,120,124,128,
%U A354098 132,134,136,140,142,144,148,152,156,158,160,162,164,166,168,172,176,180,184,188,192,196,200,204,206,208,212
%N A354098 Numbers k such that the cototient of k (= k-phi(k)) is a multiple of 4.
%C A354098 Union of {1}, A008586 \ {0, 4} and A196445 \ {2}. - _Amiram Eldar_, Dec 21 2023
%t A354098 Select[Range[200], Divisible[# - EulerPhi[#], 4] &] (* _Amiram Eldar_, May 17 2022 *)
%o A354098 (PARI)
%o A354098 A354097(n) = (0==((n-eulerphi(n))%4));
%o A354098 isA354098(n) = A354097(n);
%Y A354098 Cf. A000010, A010873, A051953, A354097 (characteristic function).
%Y A354098 Cf. also A292763, A354038.
%Y A354098 Cf. A008586, A196445.
%K A354098 nonn
%O A354098 1,2
%A A354098 _Antti Karttunen_, May 17 2022