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A262580
Concatenation of the numbers from 1 to n but omitting 10.
0
1, 12, 123, 1234, 12345, 123456, 1234567, 12345678, 123456789, 12345678911, 1234567891112, 123456789111213, 12345678911121314, 1234567891112131415, 123456789111213141516, 12345678911121314151617, 1234567891112131415161718, 123456789111213141516171819, 12345678911121314151617181920
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OFFSET
1,2
COMMENTS
The smallest prime in this sequence is the 61457-digit (probable) prime a(14512) = 123456789111213...14513 found by David Broadhurst on Sep 28 2015.
LINKS
Table of n, a(n) for n=1..19.
MATHEMATICA
DeleteDuplicates[Table[FromDigits[Flatten[IntegerDigits[Complement[Range[n], {10}]]]], {n, 20}]] (* Robert Price, Nov 05 2018 *)
CROSSREFS
Cf. A007908, A262299, A262571-A262582.
See A262300 for more about this problem.
Sequence in context: A007908 A262582 A262581 * A262579 A057932 A262578
Adjacent sequences: A262577 A262578 A262579 * A262581 A262582 A262583
KEYWORD
nonn,base
AUTHOR
N. J. A. Sloane, Sep 25 2015
STATUS
approved

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Last modified January 22 12:47 EST 2025. Contains 380121 sequences.
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