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%I #33 Nov 05 2018 17:25:06
%S 1,12,123,1234,12345,123456,1234567,12345679,1234567910,123456791011,
%T 12345679101112,1234567910111213,123456791011121314,
%U 12345679101112131415,1234567910111213141516,123456791011121314151617,12345679101112131415161718,1234567910111213141516171819,123456791011121314151617181920
%N Concatenation of the numbers from 1 to n but omitting 8.
%C 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.
%C No other primes through a(10000). - _Robert Price_, Nov 04 2018
%t Module[{nn=30, c}, c=Drop[Range[nn], {8}]; Table[FromDigits[Flatten[IntegerDigits/@Take[c, n]]], {n, nn-1}]] (* _Vincenzo Librandi_, Nov 05 2018 *)
%Y Cf. A007908, A262299, A262300, A262571-A262582.
%Y See A262300 for more about this problem.
%K nonn,base
%O 1,2
%A _N. J. A. Sloane_, Sep 25 2015
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