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Base 10 numbers d_1 d_2 ... d_k such that the digits d_i are distinct and not zero, and Sum_{i=1..k-1} d_i^i = d_k^k.
1

%I #4 Oct 05 2013 22:57:59

%S 42,93,253,712,6312,9823,714523,781523

%N Base 10 numbers d_1 d_2 ... d_k such that the digits d_i are distinct and not zero, and Sum_{i=1..k-1} d_i^i = d_k^k.

%e 6312 is in the sequence because 6^1+3^2+1^3=2^4, and 781523 is in the sequence because 7^1+8^2+1^3+5^4+2^5=3^6.

%t okQ[l_List] := Module[{lp= l^Range[Length[l]]}, Plus @@ Most[lp] == Last[lp]]

%t Sort[FromDigits/@Select[Flatten[Table[Permutations/@Subsets[Range[9],{i} ],{i,2,9}],2],okQ]]

%K nonn,base,fini,full

%O 1,1

%A _Harvey P. Dale_, May 01 2010, May 04 2010