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A087052 Lunar triangular numbers: 0+1+2+3+...+n, where + is lunar addition.

%I A087052 #21 Sep 14 2017 15:28:14
%S A087052 0,1,2,3,4,5,6,7,8,9,19,19,19,19,19,19,19,19,19,19,29,29,29,29,29,29,
%T A087052 29,29,29,29,39,39,39,39,39,39,39,39,39,39,49,49,49,49,49,49,49,49,49,
%U A087052 49,59,59,59,59,59,59,59,59,59,59,69,69,69,69,69,69,69,69,69,69,79,79,79,79,79,79,79,79,79,79,89,89,89,89,89,89,89,89,89,89,99,99,99,99,99,99,99,99,99,99,199,199,199,199,199,199,199,199,199,199,199,199,199,199,199,199,199,199,199,199,199
%N A087052 Lunar triangular numbers: 0+1+2+3+...+n, where + is lunar addition.
%C A087052 Differs from A087121 after 100 terms.
%C A087052 If duplicates are removed we get A051885. - _N. J. A. Sloane_, Jan 25 2011
%H A087052 D. Applegate, <a href="/A087061/a087061.txt">C program for lunar arithmetic and number theory</a> [Note: we have now changed the name from "dismal arithmetic" to "lunar arithmetic" - the old name was too depressing]
%H A087052 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]
%H A087052 D. Applegate, M. LeBrun, N. J. A. Sloane, <a href="https://cs.uwaterloo.ca/journals/JIS/VOL14/Sloane/carry2.html">Dismal Arithmetic</a>, J. Int. Seq. 14 (2011) # 11.9.8.
%H A087052 <a href="/index/Di#dismal">Index entries for sequences related to dismal (or lunar) arithmetic</a>
%p A087052 (Continuing from A087062) dt := proc(n) local i,t1; t1 := 0; for i from 1 to n do t1 := dadd(t1,i); od: t1; end;
%Y A087052 Cf. A051885.
%K A087052 nonn
%O A087052 0,3
%A A087052 Marc LeBrun and _N. J. A. Sloane_, Oct 19 2003