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Least multiple of n such that deleting the first r most significant digits yields a number divisible by n-r, for r = 0 to n-2.
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%I #6 Mar 29 2015 19:51:46

%S 1,12,114,1120,11120,111120,1111180,11111600,111120840,1111120840,

%T 11111216600,111111216600,1111132216480,11111171444240,

%U 111111171444240,1111111171444240,11111111177210000,111111111177210000

%N Least multiple of n such that deleting the first r most significant digits yields a number divisible by n-r, for r = 0 to n-2.

%e a(5) = 11120, 5 divides 11120, 4 divides 1120, 3 divides 120, 2 divides 20.

%t f[n_] := Block[{k = n*Ceiling[(10^n - 1)/(9n)]}, While[ Union[ Table[ Mod[ Mod[k, 10^j], j], {j, n}]] != {0}, k += n]; k]; Table[ f[n], {n, 18}] (* _Robert G. Wilson v_, Sep 24 2004 *)

%Y a(n) >= R_n (A002275).

%K base,nonn

%O 1,2

%A _Amarnath Murthy_, Nov 27 2003

%E Edited, corrected and extended by _Robert G. Wilson v_, Sep 24 2004