A043037 Base-10 palindromes that start with 2.

2, 22, 202, 212, 222, 232, 242, 252, 262, 272, 282, 292, 2002, 2112, 2222, 2332, 2442, 2552, 2662, 2772, 2882, 2992, 20002, 20102, 20202, 20302, 20402, 20502, 20602, 20702, 20802, 20902, 21012, 21112, 21212, 21312, 21412, 21512, 21612, 21712, 21812, 21912

Offset

1,1

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]] == 2 && palQ[#, 10] &] (* T. D. Noe, Mar 12 2013 *)
Select[Range[22000], PalindromeQ[#]&&IntegerDigits[#][[1]]==2&] (* Harvey P. Dale, Feb 21 2024 *)

Prog

(PARI) isok(n) = (d=digits(n)) && (d[1]==2) && (Vecrev(d)==d); \\ Michel Marcus, Aug 22 2015

Crossrefs

Cf. A002113.

Sequence in context: A007613 A346796 A279801 * A058441 A255043 A359856

Adjacent sequences: A043034 A043035 A043036 * A043038 A043039 A043040

Keyword

nonn,base

Author

Clark Kimberling

Status

approved