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Palindromic cyclops numbers.
10

%I #12 Dec 03 2022 19:13:08

%S 0,101,202,303,404,505,606,707,808,909,11011,12021,13031,14041,15051,

%T 16061,17071,18081,19091,21012,22022,23032,24042,25052,26062,27072,

%U 28082,29092,31013,32023,33033,34043,35053,36063,37073,38083

%N Palindromic cyclops numbers.

%C For prime entries in the sequence see A136098. - _Lekraj Beedassy_, Mar 15 2008, May 21 2008

%H Robert Israel, <a href="/A138131/b138131.txt">Table of n, a(n) for n = 1..10000</a>

%e 101 is a member because 101 is a palindromic number A002113 and also a cyclops number A134808.

%p f:= proc(n,d) local L,m,k;

%p L:= convert(9^d+n,base,9);

%p add((1+L[d+1-i])*(10^(i-1)+10^(2*d+1-i)),i=1..d)

%p end proc:

%p seq(seq(f(n,d),n=0..9^d-1),d=0..2); # _Robert Israel_, Feb 18 2018

%t Join[{0},Flatten[Table[Select[Range[10^(2n),10^(2n+1)-1],PalindromeQ[ #] && DigitCount[ #,10,0]==1&&IntegerDigits[#][[(IntegerLength[#]+1)/2]]==0&],{n,2}]]] (* _Harvey P. Dale_, Dec 03 2022 *)

%Y Cf. A002113, A002385, A134808.

%K base,easy,nonn

%O 1,2

%A _Omar E. Pol_, Mar 09 2008