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Numbers that are palindromic and divisible by 5.
4

%I #13 Nov 29 2015 10:03:11

%S 5,55,505,515,525,535,545,555,565,575,585,595,5005,5115,5225,5335,

%T 5445,5555,5665,5775,5885,5995,50005,50105,50205,50305,50405,50505,

%U 50605,50705,50805,50905,51015,51115,51215,51315,51415,51515,51615,51715,51815,51915

%N Numbers that are palindromic and divisible by 5.

%C Or, numbers that are palindromic and begin with 5.

%H Jaroslav Krizek, <a href="/A043040/b043040.txt">Table of n, a(n) for n = 1..2222</a>

%t palQ[n_Integer, base_Integer] := Module[{idn = IntegerDigits[n, base]}, idn == Reverse[idn]]; Select[Range[0, 100000], IntegerDigits[#][[1]] == 5 && palQ[#, 10] &] (* _T. D. Noe_, Mar 12 2013 *)

%t Select[5*Range[11000],IntegerDigits[#]==Reverse[IntegerDigits[#]]&] (* _Harvey P. Dale_, Nov 29 2015 *)

%K nonn,base

%O 1,1

%A _Clark Kimberling_