%I #11 Oct 09 2023 12:53:58
%S 9,91,912,9213,92314,931415,9341516,94151617,945161718,9516171819,
%T 95617181920,961718192021,9671819202122,97181920212223,
%U 978192021222324,9819202122232425,98920212223242526,992021222324252627,9922122232425262728,99222223242526272829,992222324252627282930
%N a(n) is the largest number that can be obtained by deleting n digits from A007908(n).
%C Inspired by the Example 1.1 at pp. 1-2 in Andreescu and Feng (see References).
%D Titu Andreescu and Zuming Feng, A Path to Combinatorics for Undergraduates: Counting Strategies, Birkhäuser, Boston, 2004.
%F a(n) mod 10^A055642(n) = n, for n > 11.
%Y Cf. A007908, A011557, A055642, A366394 (smallest).
%K nonn,base,easy
%O 10,1
%A _Stefano Spezia_, Oct 08 2023
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