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%I #28 Oct 18 2014 09:15:41
%S 0,1,1,2,2,2,4,3,2,5,4,3,6,6,3,7,5,7,7,6,5,10,10,5,7,8,5,12,11,9,12,5,
%T 8,13,9,8,12,16,8,14,11,12,16,12,10,19,15,11,11,9,10,19,18,17,18,13,9,
%U 23,14,15,21,19,14,19,12,18,16,19,17,26,17,11,20,16,15,21,13,26,24,13
%N a(n) = number of nontrivial reverse multipliers for base n.
%C If there is a number m such that the reversal of m in base n is c times m, then c is called a reverse multiplier for n. For example, 2 is a reverse multiplier for base n=5, since 8 (base 10) = 13 (base 5), and 2*8 = 16 (base 10) = 31 (base 5).
%C The trivial reverse multiplier 1 is excluded.
%H N. J. A. Sloane, <a href="/A222819/b222819.txt">Table of n, a(n) for n = 2..100</a>
%H N. J. A. Sloane, <a href="http://arxiv.org/abs/1307.0453">2178 And All That</a>, Fib. Quart., 52 (2014), 99-120.
%H Anne Ludington Young, <a href="http://www.fq.math.ca/Scanned/30-2/ludington1.pdf">k-Reverse multiples</a>, Fib. Q., 30 (1992), 126-132.
%Y Cf. A214927, A222817, A222818, A222820.
%Y See A214927 for other cross-references.
%K nonn,base
%O 2,4
%A _N. J. A. Sloane_, Mar 13 2013
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