A043078 a(n)=(s(n)+2)/9, where s(n)=n-th base 9 palindrome that starts with 7.

1, 8, 64, 65, 66, 67, 68, 69, 70, 71, 72, 568, 578, 588, 598, 608, 618, 628, 638, 648, 5104, 5113, 5122, 5131, 5140, 5149, 5158, 5167, 5176, 5186, 5195, 5204, 5213, 5222, 5231, 5240, 5249, 5258, 5268, 5277, 5286, 5295, 5304, 5313

Offset: 1

Author

Clark Kimberling

Keywords

• nonn
• base

Links

• Harvey P. Dale, Table of n, a(n) for n = 1..1600

Programs

Mathematica

(#+2)/9&/@Select[Range[100000],IntegerDigits[#,9][[1]]==7&&PalindromeQ[IntegerDigits[#,9]]&] (* Harvey P. Dale, Jun 21 2025 *)