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%I #31 Aug 06 2014 17:24:02
%S 0,11,12,13,14,15,16,17,18,19,110,111,112,113,114,115,116,117,118,119,
%T 120,121,122,123,124,125,126,127,128,129,130,131,132,133,134,135,136,
%U 137,138,139,140,141,142,143,144,145,146,147,148,149,150
%N Lunar product 19*n.
%C Since 19 is the smallest lunar prime, this is a kind of lunar analog of the even numbers.
%C As the b-file shows, this sequence is not monotonic and contains repetitions.
%H N. J. A. Sloane, <a href="/A162672/b162672.txt">Table of n, a(n) for n = 0..10000</a>
%H D. Applegate, M. LeBrun and N. J. A. Sloane, <a href="http://arxiv.org/abs/1107.1130">Dismal Arithmetic</a> [Note: we have now changed the name from "dismal arithmetic" to "lunar arithmetic" - the old name was too depressing]
%F For a two-digit number n, the lunar product 19*n is obtained by putting a 1 in front of n.
%e 19 * 3 = 13, so 13 is a member. 1109 has just two divisors, 9 and 109, so 1109 is not a member.
%Y Cf. A087062, A078645.
%K nonn,base
%O 0,2
%A Emilie Hogan, Dennis Hou, Kellen Myers and _N. J. A. Sloane_, Apr 09 2010
%E Entry revised by _N. J. A. Sloane_, May 28 2011, to correct errors in some of the comments
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