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Numbers (not ending in 0) which are 9 times their digit-reversal.
7

%I #12 Oct 12 2017 16:28:38

%S 9801,98901,989901,9899901,98019801,98999901,980109801,989999901,

%T 9801009801,9890198901,9899999901,98010009801,98901098901,98999999901,

%U 980100009801,980198019801,989010098901,989901989901,989999999901,9801000009801,9801989019801,9890100098901

%N Numbers (not ending in 0) which are 9 times their digit-reversal.

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

%H Ray Chandler, <a href="/A222814/b222814.txt">Table of n, a(n) for n = 1..10000</a>

%H N. J. A. Sloane, <a href="http://arxiv.org/abs/1307.0453">2178 And All That</a>, Fib. Quart., 52 (2014), 99-120.

%t okQ[t_]:=t==Reverse[t]&&First[t]!=0&&Min[Length/@Split[t]]>1; Sort[ Flatten[ (9*99)#&/@Flatten[Table[FromDigits/@Select[Tuples[{0,1},n],okQ],{n,12}]]]] (* _Harvey P. Dale_, Jul 03 2013 *)

%Y Equals 9*A001232.

%K nonn,base

%O 1,1

%A _N. J. A. Sloane_, Mar 11 2013