A043040 Numbers that are palindromic and divisible by 5.

0, 5, 55, 505, 515, 525, 535, 545, 555, 565, 575, 585, 595, 5005, 5115, 5225, 5335, 5445, 5555, 5665, 5775, 5885, 5995, 50005, 50105, 50205, 50305, 50405, 50505, 50605, 50705, 50805, 50905, 51015, 51115, 51215, 51315, 51415, 51515, 51615, 51715, 51815, 51915

Offset: 1

Author

Clark Kimberling

Keywords

• nonn
• base

Comments

Or, 0 and numbers that are palindromic and begin with 5.

Links

• Jaroslav Krizek, Table of n, a(n) for n = 1..2223

Crossrefs

Intersection of A002113 and A008587.

Cf. A029951, A045638, A045639, A045641, A045642, A045643, A045644, A083852.

Programs

Mathematica

palQ[n_Integer, base_Integer] := Module[{idn = IntegerDigits[n, base]}, idn == Reverse[idn]];
Join[{0},Select[Range[5,100000,5], IntegerDigits[#][[1]] == 5 && palQ[#, 10] &]] (* T. D. Noe, Mar 12 2013 *)
Select[5*Range[0,11000],IntegerDigits[#]==Reverse[IntegerDigits[#]]&] (* Harvey P. Dale, Nov 29 2015 *)

Extensions

Edited to include a(1) = 0 by Paolo Xausa, Jul 07 2025