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A354694 Least Euler pseudoprime to base 2 through base prime(n). 1

%I #5 Jun 04 2022 08:00:13

%S 341,1729,1729,46657,46657,162401,399001,399001,399001,399001,488881,

%T 3057601,3057601,3828001,3828001,3828001,3828001,3828001,3828001,

%U 3828001,3828001,3828001,3828001,3828001,3828001,17098369,17098369,17098369,17098369,17236801,17236801

%N Least Euler pseudoprime to base 2 through base prime(n).

%C a(n) is coprime to A002110(n).

%H Eric Weisstein's World of Mathematics, <a href="http://mathworld.wolfram.com/EulerPseudoprime.html">Euler Pseudoprime.</a>

%o (PARI) a(n) = my(b, m, p=factorback(primes(n))); forcomposite(k=9, oo, if(gcd(k, p)==1, b=2; while((m=Mod(b, k)^(k\2)) == 1 || m == k-1, b++); if(b>prime(n), return(k))));

%Y Cf. A002110, A007324, A083876, A271221.

%K nonn

%O 1,1

%A _Jinyuan Wang_, Jun 04 2022

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Last modified August 14 15:00 EDT 2024. Contains 375165 sequences. (Running on oeis4.)