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%I #7 Dec 05 2013 19:55:52
%S 1,2,3,4,5,6,7,8,9,10,11,12,13,14,15,16,17,18,19,200,21,22,23,24,25,
%T 26,27,28,29,300,310,32,33,34,35,36,37,38,39,400,410,420,43,44,45,46,
%U 47,48,49,500,510,520,530,54,55,56,57,58,59,600,610,620,630,640,65,66,67
%N First column of A077341.
%C a(20) = 200 and not 20. Can anyone derive a formula for a(n)?
%C a(n) = n when n > 10 * floor(n/10) + floor(n/10) - 2. Otherwise it is guaranteed that n has appeared in a previous row of the triangle. - _Alonso del Arte_, Jan 07 2013
%H Hans Havermann, <a href="/A077342/b077342.txt">Table of n, a(n) for n = 1..10000</a>
%Y Cf. A077339, A077340, A077341, A077343.
%K base,easy,nonn
%O 1,2
%A _Amarnath Murthy_, Nov 05 2002