

A128668


Primes p such that p^2 divides 17^(p1)  1.


17




OFFSET

1,1


COMMENTS

Mossinghoff showed that there are no further terms up to 10^14.


LINKS

Table of n, a(n) for n=1..5.
Amir Akbary and Sahar Siavashi, The Largest Known Wieferich Numbers, INTEGERS, 18(2018), A3. See Table 1 p. 5.
Richard Fischer, Fermat quotients B^(P1) == 1 (mod P^2)
M. J. Mossinghoff, Wieferich pairs and Barker sequences, Des. Codes Cryptogr. 53 (2009), 149163.


MATHEMATICA

Select[Prime[Range[5*10^6]], Mod[ 17^(#  1)  1, #^2] == 0 &] (* G. C. Greubel, Jan 18 2018 *)


CROSSREFS

Cf. A001220, A014127, A123692, A123693, A128667, A090968, A128669, A039951.
Sequence in context: A197635 A171161 A101445 * A216977 A331426 A300191
Adjacent sequences: A128665 A128666 A128667 * A128669 A128670 A128671


KEYWORD

hard,more,nonn


AUTHOR

Alexander Adamchuk, Mar 26 2007


EXTENSIONS

The prime 478225523351 was found by Richard Fischer on Oct 25 2005
Extension corrected by Jonathan Sondow, Jun 24 2010


STATUS

approved



