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A128668 Primes p such that p^2 divides 17^(p-1) - 1. 6
2, 3, 46021, 48947, 478225523351 (list; graph; refs; listen; history; text; internal format)
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.

Richard Fischer, Fermat quotients B^(P-1) == 1 (mod P^2)

M. J. Mossinghoff, Wieferich pairs and Barker sequences, Des. Codes Cryptogr. 53 (2009), 149-163.

CROSSREFS

Cf. A001220, A014127, A123692, A123693, A128667, A090968, A128669, A039951.

Sequence in context: A197635 A171161 A101445 * A216977 A038537 A235984

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

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Last modified April 19 10:50 EDT 2014. Contains 240747 sequences.