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A245583
Wieferich prime candidates: primes of the form A242139(n)+1 also having the form {m*(2^rs - 1)/(2^r - 1)}+1.
0
293, 439, 547, 1093, 1171, 2341, 3511
OFFSET
1,1
COMMENTS
292 = 100100100, 438 = 110110110, 546 = 001000100010, 1092 = 010001000100, 1170 = 010010010010, 2340 = 100100100100, 3510 = 110110110110.
According to Dobson, all primes where m is of the form 2*(4^(r/2)-1)/3 cannot be Wieferich primes.
Triples (m, r, s) producing the terms through the formula in definition are (4, 3, 3), (6, 3, 3), (2, 4, 3), (4, 4, 3), (2, 3, 4), (4, 3, 4), (6, 3, 4).
LINKS
S. Agou, Irréductibilité des polynômes f(X^p^r-aX) sur un corps fini F_p^s, J. reine angew. Mat. 292 (1977), 191-195.
J. B. Dobson, A note on the two known Wieferich primes (Archive of the site from August 28 2011)
CROSSREFS
Sequence in context: A155140 A248210 A142284 * A252409 A251682 A251675
KEYWORD
nonn,more
AUTHOR
Felix Fröhlich, Jul 26 2014
STATUS
approved