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%I #3 Mar 30 2012 17:22:33
%S 3,5,6,9,10,14,21,22,24,29,30,33,34,36,37,38,41,42,43,46,50,51,52,57,
%T 58,59,62,66,68,69,70,73,75,78,82,84,85,86,88,90,91,93,94,98
%N Numbers n such that the Lebesgue-Nagell equation x^2 + n = y^k, with k > 2, has no integer solutions.
%t lst=Table[cnt=0; Do[x=Sqrt[y^k-n]; If[IntegerQ[x], cnt++ ], {k, 3, 20}, {y, 600}]; cnt, {n, 2, 100}]; Flatten[Position[lst, 0]]+1
%Y Cf. A094596, A094597, A094599.
%K hard,nonn
%O 1,1
%A _T. D. Noe_, May 13 2004