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%I #11 Oct 26 2016 15:24:54
%S 1,2,3,4,5,6,7,8,1,1,2,3,4,5,6,7,8,2,1,2,3,4,5,6,7,8,3,1,2,3,4,5,6,7,
%T 8,4,1,2,3,4,5,6,7,8,5,1,2,3,4,5,6,7,8,6,1,2,3,4,5,6,7,8,7,1,2,3,4,5,
%U 6,7,8,8,1,2,3,4,5,6,7,8,1,1,2,3,4,5
%N a(n) = n/9^m mod 9, where 9^m is the greatest power of 9 that divides n.
%C a(n) is the rightmost nonzero digit in the base 9 expansion of n.
%H Clark Kimberling, <a href="/A277547/b277547.txt">Table of n, a(n) for n = 1..10000</a>
%e a(11) = (11/9 mod 9) = 2.
%t Table[Mod[n/9^IntegerExponent[n, 9], 9], {n, 1, 160}]
%o (PARI) a(n) = n/9^valuation(n, 9) % 9; \\ _Michel Marcus_, Oct 20 2016
%Y Cf. A010878.
%K nonn,easy
%O 1,2
%A _Clark Kimberling_, Oct 19 2016