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%I #2 Mar 30 2012 17:26:28
%S 1,3,4,8,10,11
%N Numbers n such that the decimal expansion of 2^n+5^n contains no 2's and no 5's (probably 11 is the last term).
%e {n, 2^n+5^n}:{1,7}, {3,133}, {4,641}, {8,390881}, {10,9766649}, {11,48830173}.
%t Do[If[Intersection[IntegerDigits[p=2^n+5^n],{2,5}]=={},Print[{n,p}]],{n,0,2000}]
%Y Cf. A074600, A007496, A152493.
%K base,nonn
%O 1,2
%A _Zak Seidov_, Oct 25 2009
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