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%I #24 Sep 08 2022 08:46:14
%S 2,23,234,2345,23456,234567,2345678,23456789,2345678910,234567891011,
%T 23456789101112,2345678910111213,234567891011121314,
%U 23456789101112131415,2345678910111213141516,234567891011121314151617,23456789101112131415161718,2345678910111213141516171819
%N Concatenation of the numbers from 2 to n.
%t Table[FromDigits[Flatten[IntegerDigits[Range[2, n]]]], {n, 2, 19}] (* _Robert Price_, Oct 28 2018 *)
%o (Magma) [Seqint(Reverse(&cat[Reverse(Intseq(k)): k in [2..n]])): n in [2..20]]; // _Vincenzo Librandi_, Oct 29 2018
%o (Python)
%o def a(n): return int("".join(map(str, range(2, n+1))))
%o print([a(n) for n in range(2, 20)]) # _Michael S. Branicky_, Feb 23 2021
%Y For primes in this sequence see A089987.
%Y Cf. A007908, A262299, A262572-A262582.
%Y See A262300 for more about this problem.
%K nonn,base
%O 2,1
%A _N. J. A. Sloane_, Sep 25 2015
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