A043042 Base-10 palindromes that start with 7.

7, 77, 707, 717, 727, 737, 747, 757, 767, 777, 787, 797, 7007, 7117, 7227, 7337, 7447, 7557, 7667, 7777, 7887, 7997, 70007, 70107, 70207, 70307, 70407, 70507, 70607, 70707, 70807, 70907, 71017, 71117, 71217, 71317, 71417, 71517, 71617, 71717, 71817, 71917

Offset

1,1

Comments

Subsequence of A002113 (palindromic numbers). Union of A222727 (palindromic primes starting with a digit 7) and A222728 (palindromic composite numbers starting with a digit 7). - 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]] == 7 && palQ[#, 10] &] (* T. D. Noe, Mar 12 2013 *)
Select[Range[72000], First[IntegerDigits[#]]==7&&PalindromeQ[#]&] (* Requires Mathematica version 10 or later *) (* Harvey P. Dale, Mar 02 2018 *)

Crossrefs

Cf. A002113.

Sequence in context: A068667 A261741 A228414 * A191465 A229281 A144071

Adjacent sequences: A043039 A043040 A043041 * A043043 A043044 A043045

Keyword

nonn,base

Author

Clark Kimberling

Status

approved