|
%I #15 Feb 11 2021 21:25:00
%S 1,2,4,8,14,16,22,26,32,44,46,52,62,64,92,94,108,112,118,124,128,154,
%T 164,166,188,214,222,234,236,244,252,256,258,264,288,332,334,336,358,
%U 390,412,428,438,454,456,504,512,526,534,546,576,582,630,664,668,672
%N Numbers k such that 2^k mod k = 2^phi(k) mod phi(k).
%C Numbers k such that A015910(k) = A015910(A000010(k)). - _Michel Marcus_, Feb 11 2021
%t Select[Range[1000], PowerMod[2, #, #] == PowerMod[2, (e = EulerPhi[#]), e] &] (* _Amiram Eldar_, Feb 11 2021 *)
%o (PARI) f(n) = lift(Mod(2, n)^n); \\ A015910
%o isok(k) = f(k) == f(eulerphi(k)); \\ _Michel Marcus_, Feb 11 2021
%Y Cf. A000010, A015910.
%K easy,nonn
%O 1,2
%A _Benoit Cloitre_, Apr 03 2002
|
