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%I #8 Apr 28 2019 18:09:34
%S 11,88,11,207,2955
%N a(n) is the smallest number whose n-th power has all its digits twice.
%C There may be no further terms.
%e 11^1 = 11, 88^2 = 7744, 11^3 = 1331, 207^4 = 1836036801, 2955^5 = 225313610074846875.
%t g[n_] := Block[{k = 2}, While[ Union[ Length@ # & /@ Split@ Sort@ IntegerDigits[k^n]] != {2}, k++ ]; k]; Do[ Print@ g@ n, {n, 5}] (* _Robert G. Wilson v_, Aug 31 2007 *)
%K base,fini,nonn
%O 1,1
%A _Tanya Khovanova_, Dec 09 2006