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A262578 Concatenation of the numbers from 1 to n but omitting 8. 0
1, 12, 123, 1234, 12345, 123456, 1234567, 12345679, 1234567910, 123456791011, 12345679101112, 1234567910111213, 123456791011121314, 12345679101112131415, 1234567910111213141516, 123456791011121314151617, 12345679101112131415161718, 1234567910111213141516171819, 123456791011121314151617181920 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,2

COMMENTS

The first (probable) prime in this sequence is a(1872) = 1234567910111213...1873 (ending at 1873), a 6364-digit probable prime, too large to display here). It was found by David Broadhurst on Sep 27 2015.

No other primes through a(10000). - Robert Price, Nov 04 2018

LINKS

Table of n, a(n) for n=1..19.

MATHEMATICA

Module[{nn=30, c}, c=Drop[Range[nn], {8}]; Table[FromDigits[Flatten[IntegerDigits/@Take[c, n]]], {n, nn-1}]] (* Vincenzo Librandi, Nov 05 2018 *)

CROSSREFS

Cf. A007908, A262299, A262300, A262571-A262582.

See A262300 for more about this problem.

Sequence in context: A262580 A262579 A057932 * A262577 A132943 A262576

Adjacent sequences:  A262575 A262576 A262577 * A262579 A262580 A262581

KEYWORD

nonn,base

AUTHOR

N. J. A. Sloane, Sep 25 2015

STATUS

approved

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Last modified April 5 02:41 EDT 2020. Contains 333238 sequences. (Running on oeis4.)