%I
%S 1,2,3,2,5,2,3,6,3,10,4,16,22,6,5,6,2,10,15,20,25,30,12,6,25,2,9,2,2,
%T 20,34,28,16,22,30,44,17,46,48,20,47,44,34,32,45,24,35,28,38,50,47,24,
%U 1,50,20,36,1,34,51,20,35,34,66,28,60,38,16,32,33,50,3,28,66,66,75,12,4,26
%N Beginning with 1, the smallest positive number which when appended to the reverse concatenation of all previous terms gives a multiple of n.
%e a(2) = 2, 2 divides 12, a(3) = 3, 213 is a multiple of 3, a(4) = 2, 3212 is a multiple of 4.
%e a(11) = 4, 103632523214 == 0 (mod 11) where 103632523214 is 10363252321 followed by a 4.
%t a[1] = 1; a[n_] := a[n] = Block[{k = 1, t = Flatten[ Table[ IntegerDigits[ a[n  i]], {i, n  1}]]}, While[ Mod[ FromDigits[ Join[t, IntegerDigits[k]]], n] != 0, k++ ]; k]; Table[ a[n], {n, 78}] (* _Robert G. Wilson v_, Nov 26 2004 *)
%K base,nonn
%O 1,2
%A _Amarnath Murthy_, Nov 25 2004
%E More terms from _Robert G. Wilson v_, Nov 26 2004
