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%I #16 Jun 29 2014 10:57:33
%S 121,3751,4961,7381,11011,29161,32791,142901,228811,239701,341341,
%T 551881,566401,595441,671671,784201,856801,1016521,1237951,1335961,
%U 1433971,1804231
%N Pseudoprimes to base 3 that are not squarefree.
%C Must be divisible by the square of a Mirimanoff prime, A014127. - _Charles R Greathouse IV_, Jun 21 2014
%H Felix Fröhlich and Charles R Greathouse IV, <a href="/A244065/b244065.txt">Table of n, a(n) for n = 1..10000</a> (first 196 terms from Fröhlich)
%o (PARI) for(n=2, 10^9, if(!isprime(n) && Mod(3, n)^(n-1)==1 && !issquarefree(n), print1(n, ", ")))
%o (PARI) list(lim)=my(M=[11,1006003],v=List(),p2);for(i=1,#M,p2=M[i]^2;forstep(n=p2,lim,p2,if(Mod(3,n)^(n-1)==1,listput(v,n))));Set(v) \\ Good for lim <= 9.4 * 10^29; _Charles R Greathouse IV_, Jun 21 2014
%Y Cf. A005935, A158358, A014127.
%K nonn
%O 1,1
%A _Felix Fröhlich_, Jun 19 2014