Primes p for which exactly five bases b with 1 < b < p exist such that p is a base b Wieferich prime.

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`%I #9 Mar 07 2015 15:33:48
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`%S 653,4909,7723,9811,13691,15413,18133,18223,21061,22147,25679,29131,
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`%T 33923,35353,36913,37633,46021,57527,61819,66107,71059,72643,77867,
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`%U 79867,85061,87509,89113,96757,97213,98641,117977,118163,120247,122209,123653,126443,129061
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`%N Primes p for which exactly five bases b with 1 < b < p exist such that p is a base b Wieferich prime.
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`%C p = prime(n) such that A242830(n) = 5.
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`%o (PARI) forprime(p=1, , b=2; i=0; while(b < p, if(Mod(b, p^2)^(p-1)==1, i++); b++); if(i==5, print1(p, ", ")))
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`%Y Cf. A255203, A255204, A255205, A255206, A255207, A255209, A255210.
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`%K nonn
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`%O 1,1
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`%A _Felix FrÃ¶hlich_, Feb 17 2015
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