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A123988
Primes p such that 2^x == 3 (mod p) has no solutions.
3
3, 7, 17, 31, 41, 43, 73, 79, 89, 103, 109, 113, 127, 137, 151, 157, 199, 223, 229, 233, 241, 251, 257, 271, 277, 281, 283, 331, 337, 353, 367, 397, 401, 433, 439, 449, 457, 463, 487, 521, 569, 571, 593, 601, 607, 617, 631, 641, 673, 683, 691, 727, 733, 739, 751, 761, 809, 811, 823, 857, 881, 911
OFFSET
1,1
COMMENTS
Such primes cannot divide solutions to 2^m == 3 (mod m) (see A050259).
PROG
(Magma) lst:=[3]; for p in [5..911 by 2] do if IsPrime(p) then t:=0; e:=Ceiling(Log(2, p+1)); for x in [e..p-2] do if 2^x mod p eq 3 then t:=1; break; end if; end for; if t eq 0 then Append(~lst, p); end if; end if; end for; lst; // Arkadiusz Wesolowski, Jan 12 2021
CROSSREFS
Cf. A050259, A001915 (complement in the primes).
Sequence in context: A083991 A372082 A228567 * A006628 A068682 A292446
KEYWORD
nonn
AUTHOR
Artur Jasinski, Nov 23 2006
EXTENSIONS
Edited by Max Alekseyev, Jan 14 2007
Corrected by Max Alekseyev, Jun 08 2011
Corrected by Arkadiusz Wesolowski, Jan 12 2021
STATUS
approved