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%I #9 Jul 14 2021 10:03:22
%S 0,2,20,21,23,24,202,204,210,212,214,216,232,234,240,242,244,246,2020,
%T 2022,2023,2025,2026,2028,2040,2042,2043,2045,2046,2048,2100,2102,
%U 2103,2105,2106,2108,2120,2121,2122,2123,2125,2126,2127,2128,2140,2142,2143
%N Numbers k such that k and all its prefixes are a multiple of the difference between their length and their last digit.
%C The sequence has 1117896 terms, all beginning with 2, apart 0. The largest term is 2160088425040528890600488466.
%H Giovanni Resta, <a href="/A235500/b235500.txt">Table of n, a(n) for n = 1..10000</a>
%e 2128 is a term because 2 is divisible by (1-2), 21 by (2-1), 212 by (3-1) and 2128 by (4-8).
%t r[v_, nd_] := Block[{w=10*v, d=nd+1}, Do[ If[w < 10^4 && i != d && Mod[w, d-i] == 0, Sow@ w; r[w, d]]; w++, {i, 0, 9}]]; Union[{0,2}, Reap[r[2, 1]][[2, 1]]] (* terms < 10^4 *)
%Y Cf. A144688.
%K nonn,base,fini
%O 1,2
%A _Giovanni Resta_, Jan 11 2014
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