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%I #6 Oct 12 2022 08:59:53
%S 4,9,27,49,125,243,484,1000,2025,3969,8100,16129,32761,65025,131044,
%T 261121,524176,1046529,2096704,4190209,8386816,16769025,33547264,
%U 67092481,134212225,268402689,536848900,1073676289,2147395600,4294836225,8589767761,17179607041,34359441769
%N a(n) is the largest perfect power < 2^n.
%C Are all terms > 1000 identical to A357754?
%o (PARI) for (n=3, 35, forstep (k=2^n-1, 0, -1, if(ispower(k), print1(k,", "); break)))
%Y Cf. A000079, A001597, A357751, A357754.
%K nonn
%O 3,1
%A _Hugo Pfoertner_, Oct 12 2022