A043084 a(n)=(s(n)+5)/10, where s(n)=nth base 10 palindrome that starts with 5.

1, 6, 51, 52, 53, 54, 55, 56, 57, 58, 59, 60, 501, 512, 523, 534, 545, 556, 567, 578, 589, 600, 5001, 5011, 5021, 5031, 5041, 5051, 5061, 5071, 5081, 5091, 5102, 5112, 5122, 5132, 5142, 5152, 5162, 5172, 5182, 5192, 5203, 5213