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 A195988 Near-Wieferich primes above 10^9: primes p>10^9 such that 2^((p-1)/2) == +/-1 + A*p (mod p^2) with |A|<=100, i.e., p=prime(i) such that A258367(i)<=100. 5
 1222336487, 1259662487, 1274153897, 1494408397, 1584392531, 1586651309, 1662410923, 1817972423, 1890830857, 2062661389, 2244893621, 2332252547, 2416644757, 2461090421, 2566816313, 2570948153, 2589186937, 2709711233, 2760945133 (list; graph; refs; listen; history; text; internal format)
 OFFSET 1,1 COMMENTS There are many near-Wieferich primes below 10^9 (including Wieferich primes 1093 and 3511). However, Crandall, Dilcher and Pomerance searched and reported such primes in the interval [10^9,4*10^12]. The choice of upper bound for |A| is rather arbitrary. LINKS Felix Fröhlich, Table of n, a(n) for n = 1..139 R. Crandall, K. Dilcher and C. Pomerance, A search for Wieferich and Wilson primes, Math. Comp. Vol. 66, Num. 217 (1997), 433-449. J. Knauer and J. Richstein, The continuing search for Wieferich primes, Math. Comp. Vol. 74, Num. 251 (2005), 1559-1563. R. McIntosh, E-Mail to Paul Zimmermann PrimeGrid, Welcome to PrimeGrid's PRPNet Server (download prpclient package including wwww). PrimeGrid, Wieferich & near Wieferich primes p < 11e15 PROG (wwww) -t Wieferich -p 1e9 -P 3e15 -s 100 CROSSREFS Cf. A001220, A246568, A258367, A258368. Sequence in context: A166735 A104933 A119333 * A262996 A022250 A211770 Adjacent sequences:  A195985 A195986 A195987 * A195989 A195990 A195991 KEYWORD nonn AUTHOR Felix Fröhlich, Sep 26 2011 EXTENSIONS Edited by Max Alekseyev, Dec 21 2011 New b-file from Felix Fröhlich, Aug 26 2015 Definition amended by Felix Fröhlich, Aug 29 2015 STATUS approved

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