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%I #8 Mar 08 2020 06:47:49
%S 74,122,152,186,234,242,244,246,284,302,338,362,374,402,404,410,412,
%T 426,434,470,472,482,494,514,516,530,532,548,572,594,602,608,626,666,
%U 668,678,722,728,746,752,788,802,804,842,844,866,868,870,872,890,892,914,942
%N Even numbers k such that both k and k + 2 are nontotients (A005277).
%H Amiram Eldar, <a href="/A333100/b333100.txt">Table of n, a(n) for n = 1..10000</a>
%H Eric Weisstein's World of Mathematics, <a href="http://mathworld.wolfram.com/Nontotient.html">Nontotient</a>.
%H Wikipedia, <a href="http://en.wikipedia.org/wiki/Nontotient">Nontotient</a>.
%e 74 is a term since both 74 and 76 are nontotients.
%o (PARI) forstep(k=2, 100, 2, if(!istotient(k) && !istotient(k+2), print1(k,", ")))
%Y Cf. A005277, A063512, A231964, A306952, A333101.
%K nonn
%O 1,1
%A _Amiram Eldar_, Mar 07 2020