A043044 - OEIS

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A043044

Palindromes that start with 9.

9, 99, 909, 919, 929, 939, 949, 959, 969, 979, 989, 999, 9009, 9119, 9229, 9339, 9449, 9559, 9669, 9779, 9889, 9999, 90009, 90109, 90209, 90309, 90409, 90509, 90609, 90709, 90809, 90909, 91019, 91119, 91219, 91319, 91419, 91519, 91619, 91719, 91819, 91919

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OFFSET

1,1

COMMENTS

Subsequence of A002113 (palindromic numbers). Union of A128375 (palindromic primes starting with a digit 9) and A222729 (palindromic composite numbers starting with a digit 9). - Jaroslav Krizek, Mar 12 2013

LINKS

Jaroslav Krizek, Table of n, a(n) for n = 1..2222

MATHEMATICA

palQ[n_Integer, base_Integer] := Module[{idn = IntegerDigits[n, base]}, idn == Reverse[idn]]; Select[Range[0, 100000], IntegerDigits[#][[1]] == 9 && palQ[#, 10] &] (* T. D. Noe, Mar 12 2013 *)

Select[Range[100000], PalindromeQ[#]&&IntegerDigits[#][[1]]==9&] (* Harvey P. Dale, Oct 13 2022 *)

CROSSREFS

Sequence in context: A160946 A359078 A100681 * A222729 A069000 A250603

Adjacent sequences: A043041 A043042 A043043 * A043045 A043046 A043047

KEYWORD

nonn,base

AUTHOR

Clark Kimberling

STATUS

approved