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%I #16 May 03 2013 13:56:51
%S 127,1093,2801,19531,22621,30941,55987,88741,131071,245411,292561,
%T 346201,524287,637421,732541,797161,837931,2625641,3500201,3835261,
%U 5229043,6377551,8108731,12207031,15018571,16007041,21700501,25646167,28792661,30397351,35615581
%N Primes of the form (k^p-1)/(k-1) not having representation in the form (m^q+1)/(m+1), where k,m > 1 and p,q > 2.
%C The exponent p must be a prime p > 3. If p=3 then (k^p-1)/(k-1) = (m^q+1)/(m+1) for m=k+1 and q=3.
%C Are almost all primes of the form (k^p-1)/(k-1), where k > 1 and p > 3, in the sequence? Except 31 and 8191. See:
%C 31 = (2^5-1)/(2-1) = (5^3-1)/(5-1) = (6^3+1)/(6+1),
%C 8191 = (2^13-1)/(2-1) = (90^3-1)/(90-1) = (91^3+1)/(91+1).
%F Numbers in A085104 but not in A059055.
%Y Cf. A085104, A059055.
%K nonn
%O 1,1
%A _Thomas Ordowski_, Apr 30 2013
%E Extended by _T. D. Noe_, Apr 30 2013
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