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%I #11 Sep 22 2013 23:14:02
%S 1,1,9,8,25,50,88,297,657,1418,3212,8662,24185,64103,183718
%N Number of perfect powers with distinct digits in base n.
%e The 8 powers with unique digits in base 5 are 1, 4, 8, 9, 16, 27, 144, and 576; in base 5 these are 1, 4, 13, 14, 31, 102, 1304, and 4301.
%o (PARI) okdigs(digs) = {for (i = 1, #digs-1, for (j = i+1, #digs, if (digs[j] == digs[i], return (0);););); return (1);}
%o a(n) = {b = n; sols = Set([1]); vmax = b^b; pmax = ceil(log(vmax)/log(2)); for (p = 2, pmax, i = 2; while ((iep = i^p) < vmax, if (okdigs(digits(iep, b)), sols = Set(concat(sols, iep));); i++;);); #sols;} \\ _Michel Marcus_, Aug 19 2013
%Y Cf. A075309
%K nonn,base,more
%O 2,3
%A _Johan Särnbratt_, Apr 04 2009
%E a(11) - a(16) from _Johan Särnbratt_, Apr 21 2009
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