A069049 Numbers k such that 2^k mod k = 2^phi(k) mod phi(k).

1, 2, 4, 8, 14, 16, 22, 26, 32, 44, 46, 52, 62, 64, 92, 94, 108, 112, 118, 124, 128, 154, 164, 166, 188, 214, 222, 234, 236, 244, 252, 256, 258, 264, 288, 332, 334, 336, 358, 390, 412, 428, 438, 454, 456, 504, 512, 526, 534, 546, 576, 582, 630, 664, 668, 672

Offset

1,2

Comments

Numbers k such that A015910(k) = A015910(A000010(k)). - Michel Marcus, Feb 11 2021

Links

Table of n, a(n) for n=1..56.

Mathematica

Select[Range[1000], PowerMod[2, #, #] == PowerMod[2, (e = EulerPhi[#]), e] &] (* Amiram Eldar, Feb 11 2021 *)

Prog

(PARI) f(n) = lift(Mod(2, n)^n); \\ A015910
isok(k) = f(k) == f(eulerphi(k)); \\ Michel Marcus, Feb 11 2021

Crossrefs

Cf. A000010, A015910.

Sequence in context: A121982 A143423 A253142 * A124853 A188629 A084621

Adjacent sequences: A069046 A069047 A069048 * A069050 A069051 A069052

Keyword

easy,nonn

Author

Benoit Cloitre, Apr 03 2002

Status

approved