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Numbers n, written in base 8, with the property that if the base-8 representation of n is read backwards, the result is 5*n.
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%I #4 Mar 23 2013 05:10:18

%S 1015,11165,102515,112665,1016015,1127665,10151015,10252515,11176165,

%T 11277665,101501015,102617515,111661165,112777665,1015001015,

%U 1016016015,1025252515,1026267515,1116511165,1117526165,1126762665,1127777665

%N Numbers n, written in base 8, with the property that if the base-8 representation of n is read backwards, the result is 5*n.

%C For the decimal representations of these numbers, see A217742.

%C Theorem: There are 2^{floor(d/2)-2} terms with d base-8 digits.

%e 1015 reversed is 5101 = 5*1015 (calculating in base 8).

%Y Cf. A214927, A217742.

%K nonn,base

%O 1,1

%A _N. J. A. Sloane_, Mar 23 2013