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A052057
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Numbers k such that the decimal expansion of 2^k contains no palindromic substring except single digits.
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2
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0, 1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15, 20, 21, 22, 29, 37, 54
(list;
graph;
refs;
listen;
history;
text;
internal format)
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OFFSET
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1,3
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COMMENTS
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Sequence is probably finite. Next term, if it exists, exceeds 1170.
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LINKS
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EXAMPLE
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Record number is 2^54 = 18014398509481984.
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MATHEMATICA
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Select[Range[0, 10^3], NoneTrue[DeleteCases[Subsequences@ IntegerDigits[2^#], _?(Length[#] <= 1 &)], PalindromeQ] &] (* Michael De Vlieger, Oct 18 2021 *)
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CROSSREFS
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KEYWORD
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nonn,base,more
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AUTHOR
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EXTENSIONS
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STATUS
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approved
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