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Smallest base-b Wieferich prime larger than b, where b = prime(n).
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%I #10 Mar 22 2015 19:21:13

%S 1093,11,20771,491531,71,863,46021,43,2481757

%N Smallest base-b Wieferich prime larger than b, where b = prime(n).

%C a(10), if it exists, is larger than approximately 5.9*10^13, corresponding to the first odd Wieferich prime in base 29 (see Fischer link).

%H R. Fischer, <a href="http://www.fermatquotient.com/FermatQuotienten/FermQ_Sort.txt">Thema: Fermatquotient B^(P-1) == 1 (mod P^2)</a>

%o (PARI) forprime(b=1, 20, forprime(p=b, , if(Mod(b, p^2)^(p-1)==1, print1(p, ", "); break({1}))))

%Y Cf. A247072.

%K nonn,hard,more

%O 1,1

%A _Felix Fröhlich_, Mar 07 2015