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A043042
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Base-10 palindromes that start with 7.
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4
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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
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OFFSET
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1,1
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COMMENTS
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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
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LINKS
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MATHEMATICA
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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 *)
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CROSSREFS
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KEYWORD
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nonn,base
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AUTHOR
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STATUS
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approved
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