%I A046872
%S A046872 7,47,191,239,307,463,499,701,743,787,853,1087,1123,1301,1487,1553,
%T A046872 1567,1823,2309,2621,2843,2903,3083,3203,3319,3323,3359,3373,3541,
%U A046872 3583,3557,3617,3659,3671,3727,3769,3863,3947,4217,4327,4373,4391
%N A046872 F-primes.
%C A046872 Call the numbers in A008849 F-numbers; then a prime p is called an F-prime 
               if there exists a squarefree F-number q_1*q_2*...*q_r*p with q_1 
               < q_2 < ... < q_r < p in which the q_i's are primes but not F-primes.
%D A046872 I. Kaplansky, The challenges of Fermat, Wallis and Ozanam (and several 
               related challenges): I. Fermat's first challenge, Preprint, 2002.
%Y A046872 Cf. A008849.
%Y A046872 Sequence in context: A009219 A142185 A158914 this_sequence A152988 A009202 
               A093112
%Y A046872 Adjacent sequences: A046869 A046870 A046871 this_sequence A046873 A046874 
               A046875
%K A046872 nonn,nice
%O A046872 1,1
%A A046872 N. J. A. Sloane (njas(AT)research.att.com), Oct 05 2002