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Numbers n such that reversal(n)=(7/3)*n.
5

%I #10 Oct 12 2017 16:34:13

%S 0,3267,32967,329967,3299967,32673267,32999967,326703267,329999967,

%T 3267003267,3296732967,3299999967,32670003267,32967032967,32999999967,

%U 326700003267,326732673267,329670032967,329967329967,329999999967,3267000003267,3267329673267,3296700032967,3299670329967,3299999999967

%N Numbers n such that reversal(n)=(7/3)*n.

%C If m is in the sequence then all numbers of the form g(m,s,t) for nonnagative integers s and t are in the sequence (the function g has been defined in the sequence A101704), for example g(3267,1,1)= 326703267 is in the sequence. If n=0 or n>1 then 33*(10^n-1) is in the sequence.

%C There are Fibonacci(floor((n-2)/2)) terms with n digits, n>1 (this is essentially A103609). - _Ray Chandler_, Oct 12 2017

%H Ray Chandler, <a href="/A101706/b101706.txt">Table of n, a(n) for n = 1..10000</a>

%e g(3267,10,2) = 32670000000000326700000000003267 is in the sequence

%e because reversal(32670000000000326700000000003267) =

%e 76230000000000762300000000007623 =

%e (7/3)*32670000000000326700000000003267, g(3267,0,4) =

%e 32673267326732673267 is in the sequence because

%e reversal(32673267326732673267) = 76237623762376237623 =

%e (7/3)*32673267326732673267.

%t Do[If[FromDigits[Reverse[IntegerDigits[n]]] == (7/3)*n, Print[n]], {n, 100000000}]

%Y Cf. A101704, A101705, A001232, A008918.

%K base,nonn

%O 1,2

%A _Farideh Firoozbakht_, Jan 01 2005

%E Terms a(8) onward from _Max Alekseyev_, Aug 18 2013