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Numbers (written in base 5) which appear the same when written in base 5 and base 10/2.
2

%I #2 Mar 30 2012 18:51:29

%S 0,1,2,3,4,20,21,22,23,24,40,41,42,43,44,200,201,202,203,204,220,221,

%T 222,223,224,240,241,242,243,244,400,401,402,403,404,420,421,422,423,

%U 424,440,441,442,443,444,2000,2001,2002,2003,2004,2020,2021,2022,2023

%N Numbers (written in base 5) which appear the same when written in base 5 and base 10/2.

%C To represent a number in base b, if a digit exceeds b, subtract b and carry 1. In fractional base b/c, subtract b and carry c. The sequence consists of numbers which in base 5 have digits in {0,2,4} except that the unit digit can be any from {0,1,2,3,4}.

%e 20 (10 in decimal) appears since it is written as 20 both in base 5 and base 10/2. 30 (15 in decimal) does not since it is written as 30 in base 5 and 25 in base 10/2.

%Y Cf. A007091, A024657, A058185.

%K base,nonn

%O 0,3

%A _Henry Bottomley_, Nov 17 2000