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a(n)=(s(n)+9)/10, where s(n)=n-th base 10 palindrome that starts with 1.
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%I #7 Jul 20 2024 16:40:25

%S 1,2,11,12,13,14,15,16,17,18,19,20,101,112,123,134,145,156,167,178,

%T 189,200,1001,1011,1021,1031,1041,1051,1061,1071,1081,1091,1102,1112,

%U 1122,1132,1142,1152,1162,1172,1182,1192,1203,1213

%N a(n)=(s(n)+9)/10, where s(n)=n-th base 10 palindrome that starts with 1.

%t (#+9)/10&/@Select[Range[100000],PalindromeQ[#]&&IntegerDigits[#][[1]]==1&] (* _Harvey P. Dale_, Jul 20 2024 *)

%K nonn,base

%O 1,2

%A _Clark Kimberling_